Science Topics

<!DOCTYPE html> <html lang="en" dir="ltr" prefix="og: https://ogp.me/ns#" class="no-js"> <head> <meta charset="utf-8" /> <meta name="description" content="EPA is one of the world’s leading environmental and human health research organizations. Science provides the foundation for Agency policies, actions, and decisions made on behalf of the American people." /> <link rel="canonical" href="https://www.epa.gov/environmental-topics/science-topics" /> <link rel="shortlink" href="https://www.epa.gov/node/172685" /> <meta property="DC.title" content="Science Topics" /> <meta property="DC.description" content="EPA is one of the world’s leading environmental and human health research organizations. Science provides the foundation for Agency policies, actions, and decisions made on behalf of the American people." /> <meta property="DC.Subject.epachannel" content="Learn the Issues, Science & Technology" /> <meta property="DC.type" content="Collections and Lists" /> <meta property="DC.date.created" content="2017-03-13" /> <meta property="DC.date.modified" content="2023-12-14" /> <meta property="DC.date.reviewed" content="2024-12-13" /> <meta property="DC.creator" content="US EPA,OMS" /> <meta property="DC.language" content="en" /> <meta property="WebArea" content="Environmental Topics" /> <meta property="ContentType" content="Basic page" /> <meta property="NavigationStyle" content="sidebar_navigation" /> <meta property="og:site_name" content="US EPA" /> <meta property="og:type" content="Basic page" /> <meta property="og:url" content="https://www.epa.gov/environmental-topics/science-topics" /> <meta property="og:title" content="Science Topics | US EPA" /> <meta property="og:description" content="EPA is one of the world’s leading environmental and human health research organizations. Science provides the foundation for Agency policies, actions, and decisions made on behalf of the American people." /> <meta property="og:image" content="https://www.epa.gov/system/files/images/2022-03/epa-standard-twitter.jpg" /> <meta property="og:image:width" content="1200" /> <meta property="og:image:height" content="630" /> <meta property="og:updated_time" content="2023-12-14" /> <meta property="og:image:alt" content="U.S. Environmental Protection Agency" /> <meta property="og:country_name" content="United States of America" /> <meta property="article:published_time" content="2017-03-13T15:14:36-04:00" /> <meta property="article:modified_time" content="2023-12-14" /> <meta name="twitter:card" content="summary_large_image" /> <meta name="twitter:description" content="EPA is one of the world’s leading environmental and human health research organizations. Science provides the foundation for Agency policies, actions, and decisions made on behalf of the American people." /> <meta name="twitter:title" content="Science Topics | US EPA" /> <meta name="twitter:url" content="https://www.epa.gov/environmental-topics/science-topics" /> <meta name="twitter:image:width" content="1200" /> <meta name="twitter:image:alt" content="U.S. Environmental Protection Agency" /> <meta name="twitter:image" content="https://www.epa.gov/system/files/images/2022-03/epa-standard-twitter.jpg" /> <meta name="twitter:image:height" content="600" /> <meta name="MobileOptimized" content="width" /> <meta name="HandheldFriendly" content="true" /> <meta name="viewport" content="width=device-width, initial-scale=1.0" /> <meta http-equiv="x-ua-compatible" content="ie=edge" /> <title>Science Topics | US EPA</title> <link rel="icon" type="image/x-icon" href="/themes/epa_theme/images/favicon.ico"> <meta name="msapplication-TileColor" content="#FFFFFF"> <meta name="msapplication-TileImage" content="/themes/epa_theme/images/favicon-144.png"> <meta name="application-name" content=""> <meta name="msapplication-config" content="/themes/epa_theme/images/ieconfig.xml"> <link rel="apple-touch-icon-precomposed" sizes="196x196" href="/themes/epa_theme/images/favicon-196.png"> <link rel="apple-touch-icon-precomposed" sizes="152x152" href="/themes/epa_theme/images/favicon-152.png"> <link rel="apple-touch-icon-precomposed" sizes="144x144" href="/themes/epa_theme/images/favicon-144.png"> <link rel="apple-touch-icon-precomposed" sizes="120x120" href="/themes/epa_theme/images/favicon-120.png"> <link rel="apple-touch-icon-precomposed" sizes="114x114" href="/themes/epa_theme/images/favicon-114.png"> <link rel="apple-touch-icon-precomposed" sizes="72x72" href="/themes/epa_theme/images/favicon-72.png"> <link rel="apple-touch-icon-precomposed" href="/themes/epa_theme/images/favicon-180.png"> <link rel="icon" href="/themes/epa_theme/images/favicon-32.png" sizes="32x32"> <link rel="preload" href="/themes/epa_theme/fonts/source-sans-pro/sourcesanspro-regular-webfont.woff2" as="font" crossorigin="anonymous"> <link rel="preload" href="/themes/epa_theme/fonts/source-sans-pro/sourcesanspro-bold-webfont.woff2" as="font" crossorigin="anonymous"> <link rel="preload" href="/themes/epa_theme/fonts/source-sans-pro/sourcesanspro-italic-webfont.woff2" as="font" crossorigin="anonymous"> <link rel="preload" href="/themes/epa_theme/fonts/merriweather/Latin-Merriweather-Bold.woff2" as="font" crossorigin="anonymous"> <link rel="stylesheet" media="all" href="/themes/contrib/stable/css/system/components/ajax-progress.module.css?snbziw" /> <link rel="stylesheet" media="all" href="/themes/contrib/stable/css/system/components/align.module.css?snbziw" /> <link rel="stylesheet" media="all" href="/themes/contrib/stable/css/system/components/autocomplete-loading.module.css?snbziw" /> <link rel="stylesheet" media="all" href="/themes/contrib/stable/css/system/components/fieldgroup.module.css?snbziw" /> <link rel="stylesheet" media="all" href="/themes/contrib/stable/css/system/components/container-inline.module.css?snbziw" /> <link rel="stylesheet" media="all" href="/themes/contrib/stable/css/system/components/clearfix.module.css?snbziw" /> <link rel="stylesheet" media="all" href="/themes/contrib/stable/css/system/components/details.module.css?snbziw" /> <link rel="stylesheet" media="all" href="/themes/contrib/stable/css/system/components/hidden.module.css?snbziw" /> <link rel="stylesheet" media="all" href="/themes/contrib/stable/css/system/components/item-list.module.css?snbziw" /> <link rel="stylesheet" media="all" href="/themes/contrib/stable/css/system/components/js.module.css?snbziw" /> <link rel="stylesheet" media="all" href="/themes/contrib/stable/css/system/components/nowrap.module.css?snbziw" /> <link rel="stylesheet" media="all" href="/themes/contrib/stable/css/system/components/position-container.module.css?snbziw" /> <link rel="stylesheet" media="all" href="/themes/contrib/stable/css/system/components/progress.module.css?snbziw" /> <link rel="stylesheet" media="all" href="/themes/contrib/stable/css/system/components/reset-appearance.module.css?snbziw" /> <link rel="stylesheet" media="all" href="/themes/contrib/stable/css/system/components/resize.module.css?snbziw" /> <link rel="stylesheet" media="all" href="/themes/contrib/stable/css/system/components/sticky-header.module.css?snbziw" /> <link rel="stylesheet" media="all" href="/themes/contrib/stable/css/system/components/system-status-counter.css?snbziw" /> <link rel="stylesheet" media="all" href="/themes/contrib/stable/css/system/components/system-status-report-counters.css?snbziw" /> <link rel="stylesheet" media="all" href="/themes/contrib/stable/css/system/components/system-status-report-general-info.css?snbziw" /> <link rel="stylesheet" media="all" href="/themes/contrib/stable/css/system/components/tabledrag.module.css?snbziw" /> <link rel="stylesheet" media="all" href="/themes/contrib/stable/css/system/components/tablesort.module.css?snbziw" /> <link rel="stylesheet" media="all" href="/themes/contrib/stable/css/system/components/tree-child.module.css?snbziw" /> <link rel="stylesheet" media="all" href="/themes/contrib/stable/css/filter/filter.caption.css?snbziw" /> <link rel="stylesheet" media="all" href="/modules/contrib/entity_embed/css/entity_embed.filter.caption.css?snbziw" /> <link rel="stylesheet" media="all" href="/themes/contrib/stable/css/media/filter.caption.css?snbziw" /> <link rel="stylesheet" media="all" href="/themes/contrib/stable/css/views/views.module.css?snbziw" /> <link rel="stylesheet" media="all" href="/modules/contrib/paragraphs/css/paragraphs.unpublished.css?snbziw" /> <link rel="stylesheet" media="all" href="/themes/epa_theme/fonts/noto-sans-arabic.css?snbziw" /> <link rel="stylesheet" media="all" href="/themes/epa_theme/fonts/noto-sans-kr.css?snbziw" /> <link rel="stylesheet" media="all" href="/themes/epa_theme/fonts/noto-sans-bn.css?snbziw" /> <link rel="stylesheet" media="all" href="/themes/epa_theme/fonts/noto-sans-gu.css?snbziw" /> <link rel="stylesheet" media="all" href="/themes/epa_theme/fonts/noto-sans-sc.css?snbziw" /> <link rel="stylesheet" media="all" href="/themes/epa_theme/fonts/noto-sans-tc.css?snbziw" /> <link rel="stylesheet" media="all" href="/themes/epa_theme/css/styles.css?snbziw" /> <link rel="stylesheet" media="all" href="/themes/epa_theme/css-lib/colorbox.min.css?snbziw" />  <script>(function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-L8ZB');</script>  </head> <body class="path-node not-front node-page node-page--node-type-page" id="top"> <div class="skiplinks" role="navigation" aria-labelledby="skip-to-main"> <a id="skip-to-main" href="#main" class="skiplinks__link visually-hidden focusable">Skip to main content</a> </div>  <noscript><iframe src="https://www.googletagmanager.com/ns.html?id=GTM-L8ZB" height="0" width="0" style="display:none;visibility:hidden"></iframe></noscript>  <div class="dialog-off-canvas-main-canvas" data-off-canvas-main-canvas> <section class="usa-banner" aria-label="Official website of the United States government"> <div class="usa-accordion"> <header class="usa-banner__header"> <div class="usa-banner__inner"> <div class="grid-col-auto"> <img class="usa-banner__header-flag" aria-hidden="true" src="/themes/epa_theme/images/us_flag_small.png" alt="U.S. flag" height="11px" width="16px" /> </div> <div class="grid-col-fill tablet:grid-col-auto" aria-hidden="true"> <p class="usa-banner__header-text">An official website of the United States government</p> <p class="usa-banner__header-action">Here’s how you know</p></div> <button type="button" class="usa-accordion__button usa-banner__button" aria-expanded="false" aria-controls="gov-banner"> <span class="usa-banner__button-text">Here’s how you know</span> </button> </div> </header> <div class="usa-banner__content usa-accordion__content" id="gov-banner"> <div class="grid-row grid-gap-lg"> <div class="usa-banner__guidance tablet:grid-col-6"> <img class="usa-banner__icon usa-media-block__img" src="/themes/epa_theme/images/icon-dot-gov.svg" alt="Dot gov"> <div class="usa-media-block__body"> <p> <strong>Official websites use .gov</strong> <br> A <strong>.gov</strong> website belongs to an official government organization in the United States. </p> </div> </div> <div class="usa-banner__guidance tablet:grid-col-6"> <img class="usa-banner__icon usa-media-block__img" src="/themes/epa_theme/images/icon-https.svg" alt="HTTPS"> <div class="usa-media-block__body"> <p> <strong>Secure .gov websites use HTTPS</strong> <br> A <strong>lock</strong> (<span class="icon-lock"><svg xmlns="http://www.w3.org/2000/svg" width="52" height="64" viewBox="0 0 52 64" class="usa-banner__lock-image" role="img" aria-labelledby="banner-lock-title banner-lock-description"><title id="banner-lock-title">Lock</title><desc id="banner-lock-description">A locked padlock</desc><path fill="#000000" fill-rule="evenodd" d="M26 0c10.493 0 19 8.507 19 19v9h3a4 4 0 0 1 4 4v28a4 4 0 0 1-4 4H4a4 4 0 0 1-4-4V32a4 4 0 0 1 4-4h3v-9C7 8.507 15.507 0 26 0zm0 8c-5.979 0-10.843 4.77-10.996 10.712L15 19v9h22v-9c0-6.075-4.925-11-11-11z"/></svg></span>) or <strong>https://</strong> means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites. </p> </div> </div> </div> </div> </div> </section> <div class="js-view-dom-id-epa-alerts--public"> <noscript> <div class="usa-site-alert usa-site-alert--info"> <div class="usa-alert"> <div class="usa-alert__body"> <div class="usa-alert__text"> <p>JavaScript appears to be disabled on this computer. Please <a href="/alerts">click here to see any active alerts</a>.</p> </div> </div> </div> </div> </noscript> </div> <header class="l-header js-header-search usa-header usa-header--extended"> <div class="usa-overlay"></div> <div class="l-constrain"> <div class="l-header__navbar"> <div class="l-header__branding"> <button type="button" class="l-header__search-button" aria-controls="header-search-drawer" aria-expanded="false" aria-label="Open search drawer" > <svg class="icon l-header__search-button-icon-open" aria-hidden="true"><use href="/themes/epa_theme/images/sprite.artifact.svg#magnifying-glass"></use></svg> <svg class="icon l-header__search-button-icon-close" aria-hidden="true"><use href="/themes/epa_theme/images/sprite.artifact.svg#xmark"></use></svg> </button> <a class="site-logo" href="/" aria-label="Home" title="Home" rel="home"> <span class="site-logo__image"> <svg class="site-logo__svg-main" aria-hidden="true" viewBox="0 0 454.1 154.7" xmlns="http://www.w3.org/2000/svg"><path d="m112.8 61.2c-4.8 18.6-22.9 33.3-42.9 33.3-20.1 0-38-14.7-42.9-33.4h.2s9.8 10.3-.2 0c3.1 3.1 6.2 4.4 10.7 4.4s7.7-1.3 10.7-4.4c3.1 3.1 6.3 4.5 10.9 4.4 4.5 0 7.6-1.3 10.7-4.4 3.1 3.1 6.2 4.4 10.7 4.4s7.7-1.3 10.7-4.4c3.1 3.1 6.3 4.5 10.9 4.4 4.3 0 7.4-1.2 10.5-4.3z"/><path d="m113.2 51.2c0-24-19.4-43.5-43.3-43.5-24 0-43.5 19.5-43.5 43.5h39.1c-4.8-1.8-8.1-6.3-8.1-11.6 0-7 5.7-12.5 12.5-12.5 7 0 12.7 5.5 12.7 12.5 0 5.2-3.1 9.6-7.6 11.6z"/><path d="m72.6 147c.7-36.9 29.7-68.8 66.9-70 0 37.2-30 68-66.9 70z"/><path d="m67.1 147c-.7-36.9-29.7-68.8-67.1-70 0 37.2 30.2 68 67.1 70z"/><path d="m240 10.8h-87.9v133.1h87.9v-20.4h-60.3v-36h60.3v-21h-60.3v-35h60.3z"/><path d="m272.8 66.5h27.1c9.1 0 15.2-8.6 15.1-17.7-.1-9-6.1-17.3-15.1-17.3h-25.3v112.4h-27.8v-133.1h62.3c20.2 0 35 17.8 35.2 38 .2 20.4-14.8 38.7-35.2 38.7h-36.3z"/><path d="m315.9 143.9h29.7l12.9-35h54.2l-8.1-21.9h-38.4l18.9-50.7 39.2 107.6h29.7l-53.1-133.1h-33.7z"/></svg> <svg class="site-logo__svg-text" aria-hidden="true" viewBox="0 0 595.4 154.7" xmlns="http://www.w3.org/2000/svg"><path d="m9 8.5v22.4c0 1.9.2 3.3.5 4.3s.7 1.7 1 2.2c1.2 1.4 2.5 2.4 3.9 2.9 1.5.5 2.8.7 4.1.7 2.4 0 4.2-.4 5.5-1.3 1.3-.8 2.2-1.8 2.8-2.9s.9-2.3 1-3.4.1-2 .1-2.6v-22.3h4.7v22.3 1.7c0 .7-.1 1.5-.4 2.4-.3 1.8-1.2 3.6-2.5 5.4-1.8 2.1-3.8 3.5-6 4.2-2.2.6-4 .9-5.3.9-1.8 0-3.8-.3-6.2-1.1s-4.5-2.3-6.2-4.7c-.5-.8-1-1.8-1.4-3.2-.4-1.3-.6-3.3-.6-5.9v-22z"/><path d="m43.2 22.2v-2.9l4.6.1-.1 4.1c.2-.3.4-.7.8-1.2.3-.5.8-.9 1.4-1.4s1.4-.9 2.3-1.3c.9-.3 2.1-.5 3.4-.4.6 0 1.4.1 2.4.3.9.2 1.9.6 2.9 1.2s1.8 1.5 2.4 2.6c.6 1.2.9 2.8.9 4.7l-.4 17-4.6-.1.4-16c0-.9 0-1.7-.2-2.4-.1-.7-.5-1.3-1.1-1.9-1.2-1.2-2.6-1.8-4.3-1.8s-3.1.5-4.4 1.7-2 3.1-2.1 5.7l-.3 14.5-4.5-.1z"/><path d="m72.9 8.6h5.5v5.1h-5.5zm.5 10.9h4.6v25.1h-4.6z"/><path d="m83.5 19.4h4.3v-5.3l4.5-1.5v6.8h5.4v3.4h-5.4v15.1c0 .3 0 .6.1 1 0 .4.1.7.4 1.1.2.4.5.6 1 .8.4.3 1 .4 1.8.4 1 0 1.7-.1 2.2-.2v3.7c-.9.2-2.1.3-3.8.3-2.1 0-3.6-.4-4.6-1.2s-1.5-2.2-1.5-4.2v-16.8h-4.3v-3.4z"/><path d="m106.6 32.9c-.1 2.6.5 4.8 1.7 6.5 1.1 1.7 2.9 2.6 5.3 2.6 1.5 0 2.8-.4 3.9-1.3 1-.8 1.6-2.2 1.8-4h4.6c0 .6-.2 1.4-.4 2.3-.3 1-.8 2-1.7 3-.2.3-.6.6-1 1-.5.4-1 .7-1.7 1.1s-1.5.6-2.4.8c-.9.3-2 .4-3.3.4-7.6-.2-11.3-4.5-11.3-12.9 0-2.5.3-4.8 1-6.8s2-3.7 3.8-5.1c1.2-.8 2.4-1.3 3.7-1.6 1.3-.2 2.2-.3 3-.3 2.7 0 4.8.6 6.3 1.6s2.5 2.3 3.1 3.9c.6 1.5 1 3.1 1.1 4.6.1 1.6.1 2.9 0 4h-17.5m12.9-3c0-.3 0-.7 0-1.1s0-.8-.1-1.2c-.1-.9-.4-1.7-.8-2.5s-1-1.5-1.8-2c-.9-.5-2-.8-3.4-.8-.8 0-1.5.1-2.3.3s-1.5.7-2.2 1.3-1.2 1.3-1.6 2.3-.7 2.2-.8 3.6h13z"/><path d="m148.6 8.6h4.6v32.1c0 1 .1 2.3.2 4h-4.6l-.1-4c-.2.3-.4.7-.7 1.2s-.8 1-1.4 1.5c-1 .7-2 1.2-3.1 1.4-.5.1-1 .2-1.5.3s-.9.1-1.4.1c-.4 0-.8 0-1.3-.1s-1.1-.2-1.7-.3c-1.1-.3-2.3-.9-3.4-1.8s-2.1-2.2-2.9-3.8c-.8-1.7-1.2-3.9-1.2-6.6.1-4.8 1.2-8.3 3.4-10.5 2.1-2.1 4.7-3.2 7.6-3.2 1.3 0 2.4.2 3.4.5.9.3 1.6.7 2.2 1.2.6.4 1 .9 1.3 1.4s.6.8.7 1.1zm.1 23.1c0-1.9-.2-3.3-.5-4.4-.4-1.1-.8-2-1.4-2.6-.5-.7-1.2-1.3-2-1.8-.9-.5-2-.7-3.3-.7-1.7 0-2.9.5-3.8 1.3s-1.6 1.9-2 3.1-.7 2.3-.7 3.4c-.1 1.1-.2 1.9-.1 2.4 0 1.1.1 2.2.3 3.4.2 1.1.5 2.2 1 3.1.5 1 1.2 1.7 2 2.3.9.6 2 .9 3.3.9 1.8 0 3.2-.5 4.2-1.4 1-.8 1.7-1.8 2.1-3s.7-2.4.8-3.4c.1-1.4.1-2.1.1-2.6z"/><path d="m179.6 34.1c0 .6.1 1.3.3 2.1.1.8.5 1.6 1 2.3.5.8 1.4 1.4 2.5 1.9s2.7.8 4.7.8c1.8 0 3.3-.3 4.4-.8s1.9-1.1 2.5-1.8 1-1.5 1.1-2.2.2-1.2.2-1.7c0-1-.2-1.9-.5-2.6-.4-.6-.9-1.2-1.6-1.6-1.4-.8-3.4-1.4-5.9-2-4.9-1.1-8.1-2.2-9.5-3.2s-2.3-2.2-2.9-3.5c-.6-1.2-.8-2.4-.8-3.6.1-3.7 1.5-6.4 4.2-8.1 2.6-1.7 5.7-2.5 9.1-2.5 1.3 0 2.9.2 4.8.5 1.9.4 3.6 1.4 5 3 .5.5.9 1.1 1.2 1.7.3.5.5 1.1.6 1.6.2 1.1.3 2.1.3 2.9h-5c-.2-2.2-1-3.7-2.4-4.5-1.5-.7-3.1-1.1-4.9-1.1-5.1.1-7.7 2-7.8 5.8 0 1.5.5 2.7 1.6 3.5 1 .8 2.6 1.4 4.7 1.9 4 1 6.7 1.8 8.1 2.2.8.2 1.4.5 1.8.7.5.2 1 .5 1.4.9.8.5 1.4 1.1 1.9 1.8s.8 1.4 1.1 2.1c.3 1.4.5 2.5.5 3.4 0 3.3-1.2 6-3.5 8-2.3 2.1-5.8 3.2-10.3 3.3-1.4 0-3.2-.3-5.4-.8-1-.3-2-.7-3-1.2-.9-.5-1.8-1.2-2.5-2.1-.9-1.4-1.5-2.7-1.7-4.1-.3-1.3-.4-2.4-.3-3.2h5z"/><path d="m205.7 19.4h4.3v-5.3l4.5-1.5v6.8h5.4v3.4h-5.4v15.1c0 .3 0 .6.1 1 0 .4.1.7.4 1.1.2.4.5.6 1 .8.4.3 1 .4 1.8.4 1 0 1.7-.1 2.2-.2v3.7c-.9.2-2.1.3-3.8.3-2.1 0-3.6-.4-4.6-1.2s-1.5-2.2-1.5-4.2v-16.8h-4.4z"/><path d="m241 44.6c-.3-1.2-.5-2.5-.4-3.7-.5 1-1.1 1.8-1.7 2.4-.7.6-1.4 1.1-2 1.4-1.4.5-2.7.8-3.7.8-2.8 0-4.9-.8-6.4-2.2s-2.2-3.1-2.2-5.2c0-1 .2-2.3.8-3.7s1.7-2.6 3.5-3.7c1.4-.7 2.9-1.2 4.5-1.5 1.6-.1 2.9-.2 3.9-.2s2.1 0 3.3.1c.1-2.9-.2-4.8-.9-5.6-.5-.6-1.1-1.1-1.9-1.3s-1.6-.4-2.3-.4c-1.1 0-2 .2-2.6.5-.7.3-1.2.7-1.5 1.2s-.5.9-.6 1.4-.2.9-.2 1.2h-4.6c.1-.7.2-1.4.4-2.3.2-.8.6-1.6 1.3-2.5.5-.6 1-1 1.7-1.3.6-.3 1.3-.6 2-.8 1.5-.4 2.8-.6 4.2-.6 1.8 0 3.6.3 5.2.9s2.8 1.6 3.4 2.9c.4.7.6 1.4.7 2s.1 1.2.1 1.8l-.2 12c0 1 .1 3.1.4 6.3h-4.2m-.5-12.1c-.7-.1-1.6-.1-2.6-.1-.5 0-1.2 0-2.1 0-1 .1-2 .3-3 .6s-1.9.8-2.6 1.5c-.8.7-1.2 1.7-1.2 3 0 .4.1.8.2 1.3s.4 1 .8 1.5.9.8 1.6 1.1 1.5.5 2.5.5c2.3 0 4.1-.9 5.2-2.7.5-.8.8-1.7 1-2.7.1-.9.2-2.2.2-4z"/><path d="m250.2 19.4h4.3v-5.3l4.5-1.5v6.8h5.4v3.4h-5.4v15.1c0 .3 0 .6.1 1 0 .4.1.7.4 1.1.2.4.5.6 1 .8.4.3 1 .4 1.8.4 1 0 1.7-.1 2.2-.2v3.7c-.9.2-2.1.3-3.8.3-2.1 0-3.6-.4-4.6-1.2s-1.5-2.2-1.5-4.2v-16.8h-4.3v-3.4z"/><path d="m273.3 32.9c-.1 2.6.5 4.8 1.7 6.5 1.1 1.7 2.9 2.6 5.3 2.6 1.5 0 2.8-.4 3.9-1.3 1-.8 1.6-2.2 1.8-4h4.6c0 .6-.2 1.4-.4 2.3-.3 1-.8 2-1.7 3-.2.3-.6.6-1 1-.5.4-1 .7-1.7 1.1s-1.5.6-2.4.8c-.9.3-2 .4-3.3.4-7.6-.2-11.3-4.5-11.3-12.9 0-2.5.3-4.8 1-6.8s2-3.7 3.8-5.1c1.2-.8 2.4-1.3 3.7-1.6 1.3-.2 2.2-.3 3-.3 2.7 0 4.8.6 6.3 1.6s2.5 2.3 3.1 3.9c.6 1.5 1 3.1 1.1 4.6.1 1.6.1 2.9 0 4h-17.5m12.9-3c0-.3 0-.7 0-1.1s0-.8-.1-1.2c-.1-.9-.4-1.7-.8-2.5s-1-1.5-1.8-2c-.9-.5-2-.8-3.4-.8-.8 0-1.5.1-2.3.3s-1.5.7-2.2 1.3-1.2 1.3-1.6 2.3-.7 2.2-.8 3.6h13z"/><path d="m301 37.2c0 .5.1 1 .2 1.4.1.5.4 1 .8 1.5s.9.8 1.6 1.1 1.6.5 2.7.5c1 0 1.8-.1 2.5-.3s1.3-.6 1.7-1.2c.5-.7.8-1.5.8-2.4 0-1.2-.4-2-1.3-2.5s-2.2-.9-4.1-1.2c-1.3-.3-2.4-.6-3.6-1-1.1-.3-2.1-.8-3-1.3s-1.5-1.2-2-2.1c-.5-.8-.8-1.9-.8-3.2 0-2.4.9-4.2 2.6-5.6 1.7-1.3 4-2 6.8-2.1 1.6 0 3.3.3 5 .8 1.7.6 2.9 1.6 3.7 3.1.4 1.4.6 2.6.6 3.7h-4.6c0-1.8-.6-3-1.7-3.5-1.1-.4-2.1-.6-3.1-.6-.2 0-.5 0-1 0s-1.1.2-1.7.4-1.1.5-1.5 1.1c-.5.5-.7 1.2-.7 2.1 0 1.1.5 1.9 1.3 2.3.7.4 1.5.7 2.1.9 3.3.7 5.6 1.3 6.9 1.8 1.3.4 2.2 1 2.8 1.7.7.7 1.1 1.4 1.4 2.2s.4 1.6.4 2.5c0 1.4-.3 2.7-.9 3.8s-1.4 2-2.4 2.6c-1.1.6-2.2 1-3.4 1.3s-2.5.4-3.8.4c-2.5 0-4.7-.6-6.6-1.8-1.8-1.2-2.8-3.3-2.9-6.3z"/><path d="m3.4 58.5h21.9v4.2h-17.1v11.3h16.3v4.2h-16.3v12.1h17.5v4.3h-22.3z"/><path d="m34.7 72.4-.1-2.9h4.6v4.1c.2-.3.4-.8.7-1.2.3-.5.8-1 1.3-1.5.6-.5 1.4-1 2.3-1.3s2-.5 3.4-.5c.6 0 1.4.1 2.4.2.9.2 1.9.5 2.9 1.1s1.8 1.4 2.5 2.5c.6 1.2 1 2.7 1 4.7v17.1h-4.6v-16c0-.9-.1-1.7-.2-2.4-.2-.7-.5-1.3-1.1-1.9-1.2-1.1-2.6-1.7-4.3-1.7s-3.1.6-4.3 1.8c-1.3 1.2-2 3.1-2 5.7v14.5h-4.5z"/><path d="m60.3 69.5h5.1l7.7 19.9 7.6-19.9h5l-10.6 25.1h-4.6z"/><path d="m91.4 58.6h5.5v5.1h-5.5zm.5 10.9h4.6v25.1h-4.6z"/><path d="m106 74.7c0-1.8-.1-3.5-.3-5.1h4.6l.1 4.9c.5-1.8 1.4-3 2.5-3.7s2.2-1.2 3.3-1.3c1.4-.2 2.4-.2 3.1-.1v4.6c-.2-.1-.5-.2-.9-.2-.3 0-.8 0-1.3 0-1.3 0-2.4.2-3.3.5-.9.4-1.5.9-2 1.6-.9 1.4-1.4 3.2-1.3 5.4v13.3h-4.6v-19.9z"/><path d="m123.3 82.4c0-1.6.2-3.2.6-4.8s1.1-3 2-4.4c1-1.3 2.2-2.4 3.8-3.2s3.6-1.2 5.9-1.2c2.4 0 4.5.4 6.1 1.3 1.5.9 2.7 2 3.6 3.3s1.5 2.8 1.8 4.3c.2.8.3 1.5.4 2.2v2.2c0 3.7-1 6.9-3 9.5s-5.1 4-9.3 4c-4-.1-7-1.4-9-3.9-1.9-2.5-2.9-5.6-2.9-9.3m4.8-.3c0 2.7.6 5 1.8 6.9 1.2 2 3 3 5.6 3.1.9 0 1.8-.2 2.7-.5.8-.3 1.6-.9 2.3-1.7s1.3-1.9 1.8-3.2c.4-1.3.6-2.9.6-4.7-.1-6.4-2.5-9.6-7.1-9.6-.7 0-1.5.1-2.4.3-.8.3-1.7.8-2.5 1.6-.8.7-1.4 1.7-1.9 3-.6 1.1-.9 2.8-.9 4.8z"/><path d="m155.9 72.4-.1-2.9h4.6v4.1c.2-.3.4-.8.7-1.2.3-.5.8-1 1.3-1.5.6-.5 1.4-1 2.3-1.3s2-.5 3.4-.5c.6 0 1.4.1 2.4.2.9.2 1.9.5 2.9 1.1s1.8 1.4 2.5 2.5c.6 1.2 1 2.7 1 4.7v17.1h-4.6v-16c0-.9-.1-1.7-.2-2.4-.2-.7-.5-1.3-1.1-1.9-1.2-1.1-2.6-1.7-4.3-1.7s-3.1.6-4.3 1.8c-1.3 1.2-2 3.1-2 5.7v14.5h-4.6z"/><path d="m185.7 72.8-.1-3.3h4.6v3.6c1.2-1.9 2.6-3.2 4.1-3.7 1.5-.4 2.7-.6 3.8-.6 1.4 0 2.6.2 3.6.5.9.3 1.7.7 2.3 1.1 1.1 1 1.9 2 2.3 3.1.2-.4.5-.8 1-1.3.4-.5.9-1 1.5-1.6.6-.5 1.5-.9 2.5-1.3 1-.3 2.2-.5 3.5-.5.9 0 1.9.1 3 .3 1 .2 2 .7 3 1.3s1.7 1.5 2.3 2.7.9 2.7.9 4.6v16.9h-4.6v-16.2c0-1.1-.1-2-.2-2.5-.1-.6-.3-1-.6-1.3-.4-.6-1-1.2-1.8-1.6s-1.8-.6-3.1-.6c-1.5 0-2.7.4-3.6 1-.4.3-.8.5-1.1.9-.3.3-.6.6-.8.8-.5.8-.8 1.8-1 2.8-.1 1.1-.2 2-.1 2.6v14.1h-4.6v-16.7c0-1.6-.5-2.9-1.4-4-.9-1-2.3-1.5-4.2-1.5-1.6 0-2.9.4-3.8 1.1s-1.5 1.2-1.8 1.7c-.5.7-.8 1.5-.9 2.5-.1.9-.2 1.8-.2 2.6v14.3h-4.5z"/><path d="m236.2 82.9c-.1 2.6.5 4.8 1.7 6.5 1.1 1.7 2.9 2.6 5.3 2.6 1.5 0 2.8-.4 3.9-1.3 1-.8 1.6-2.2 1.8-4h4.6c0 .6-.2 1.4-.4 2.3-.3 1-.8 2-1.7 3-.2.3-.6.6-1 1-.5.4-1 .7-1.7 1.1s-1.5.6-2.4.8c-.9.3-2 .4-3.3.4-7.6-.2-11.3-4.5-11.3-12.9 0-2.5.3-4.8 1-6.8s2-3.7 3.8-5.1c1.2-.8 2.4-1.3 3.7-1.6 1.3-.2 2.2-.3 3-.3 2.7 0 4.8.6 6.3 1.6s2.5 2.3 3.1 3.9c.6 1.5 1 3.1 1.1 4.6.1 1.6.1 2.9 0 4h-17.5m12.8-3c0-.3 0-.7 0-1.1s0-.8-.1-1.2c-.1-.9-.4-1.7-.8-2.5s-1-1.5-1.8-2c-.9-.5-2-.8-3.4-.8-.8 0-1.5.1-2.3.3s-1.5.7-2.2 1.3-1.2 1.3-1.6 2.3-.7 2.2-.8 3.6z"/><path d="m261.4 72.4-.1-2.9h4.6v4.1c.2-.3.4-.8.7-1.2.3-.5.8-1 1.3-1.5.6-.5 1.4-1 2.3-1.3s2-.5 3.4-.5c.6 0 1.4.1 2.4.2.9.2 1.9.5 2.9 1.1s1.8 1.4 2.5 2.5c.6 1.2 1 2.7 1 4.7v17.1h-4.6v-16c0-.9-.1-1.7-.2-2.4-.2-.7-.5-1.3-1.1-1.9-1.2-1.1-2.6-1.7-4.3-1.7s-3.1.6-4.3 1.8c-1.3 1.2-2 3.1-2 5.7v14.5h-4.6z"/><path d="m288 69.4h4.3v-5.2l4.5-1.5v6.8h5.4v3.4h-5.4v15.1c0 .3 0 .6.1 1 0 .4.1.7.4 1.1.2.4.5.6 1 .8.4.3 1 .4 1.8.4 1 0 1.7-.1 2.2-.2v3.6c-.9.2-2.1.3-3.8.3-2.1 0-3.6-.4-4.6-1.2s-1.5-2.2-1.5-4.2v-16.8h-4.3v-3.4z"/><path d="m323.3 94.6c-.3-1.2-.5-2.5-.4-3.7-.5 1-1.1 1.8-1.7 2.4-.7.6-1.4 1.1-2 1.4-1.4.5-2.7.8-3.7.8-2.8 0-4.9-.8-6.4-2.2s-2.2-3.1-2.2-5.2c0-1 .2-2.3.8-3.7s1.7-2.6 3.5-3.7c1.4-.7 2.9-1.2 4.5-1.5 1.6-.1 2.9-.2 3.9-.2s2.1 0 3.3.1c.1-2.9-.2-4.8-.9-5.6-.5-.6-1.1-1.1-1.9-1.3s-1.6-.4-2.3-.4c-1.1 0-2 .2-2.6.5-.7.3-1.2.7-1.5 1.2s-.5.9-.6 1.4-.2.9-.2 1.2h-4.6c.1-.7.2-1.4.4-2.3.2-.8.6-1.6 1.3-2.5.5-.6 1-1 1.7-1.3.6-.3 1.3-.6 2-.8 1.5-.4 2.8-.6 4.2-.6 1.8 0 3.6.3 5.2.9s2.8 1.6 3.4 2.9c.4.7.6 1.4.7 2s.1 1.2.1 1.8l-.2 12c0 1 .1 3.1.4 6.3zm-.5-12.2c-.7-.1-1.6-.1-2.6-.1-.5 0-1.2 0-2.1 0-1 .1-2 .3-3 .6s-1.9.8-2.6 1.5c-.8.7-1.2 1.7-1.2 3 0 .4.1.8.2 1.3s.4 1 .8 1.5.9.8 1.6 1.1 1.5.5 2.5.5c2.3 0 4.1-.9 5.2-2.7.5-.8.8-1.7 1-2.7.1-.9.2-2.2.2-4z"/><path d="m336.4 58.6h4.6v36.1h-4.6z"/><path d="m364.1 58.5h11.7c2.1 0 3.9.1 5.5.4.8.2 1.5.4 2.2.9.7.4 1.3.9 1.8 1.6 1.7 1.9 2.6 4.2 2.6 7 0 2.7-.9 5.1-2.8 7.1-.8.9-2 1.7-3.6 2.2-1.6.6-3.9.9-6.9.9h-5.7v16.1h-4.8zm4.8 15.9h5.8c.8 0 1.7-.1 2.6-.2s1.8-.3 2.6-.7 1.5-1 2-1.9c.5-.8.8-2 .8-3.4s-.2-2.5-.7-3.3-1.1-1.3-1.9-1.7c-1.6-.5-3.1-.8-4.5-.7h-6.8v11.9z"/><path d="m393.8 74.7c0-1.8-.1-3.5-.3-5.1h4.6l.1 4.9c.5-1.8 1.4-3 2.5-3.7s2.2-1.2 3.3-1.3c1.4-.2 2.4-.2 3.1-.1v4.6c-.2-.1-.5-.2-.9-.2-.3 0-.8 0-1.3 0-1.3 0-2.4.2-3.3.5-.9.4-1.5.9-2 1.6-.9 1.4-1.4 3.2-1.3 5.4v13.3h-4.6v-19.9z"/><path d="m411.2 82.4c0-1.6.2-3.2.6-4.8s1.1-3 2-4.4c1-1.3 2.2-2.4 3.8-3.2s3.6-1.2 5.9-1.2c2.4 0 4.5.4 6.1 1.3 1.5.9 2.7 2 3.6 3.3s1.5 2.8 1.8 4.3c.2.8.3 1.5.4 2.2v2.2c0 3.7-1 6.9-3 9.5s-5.1 4-9.3 4c-4-.1-7-1.4-9-3.9-1.9-2.5-2.9-5.6-2.9-9.3m4.8-.3c0 2.7.6 5 1.8 6.9 1.2 2 3 3 5.6 3.1.9 0 1.8-.2 2.7-.5.8-.3 1.6-.9 2.3-1.7s1.3-1.9 1.8-3.2c.4-1.3.6-2.9.6-4.7-.1-6.4-2.5-9.6-7.1-9.6-.7 0-1.5.1-2.4.3-.8.3-1.7.8-2.5 1.6-.8.7-1.4 1.7-1.9 3-.7 1.1-.9 2.8-.9 4.8z"/><path d="m439.8 69.4h4.3v-5.2l4.5-1.5v6.8h5.4v3.4h-5.4v15.1c0 .3 0 .6.1 1 0 .4.1.7.4 1.1.2.4.5.6 1 .8.4.3 1 .4 1.8.4 1 0 1.7-.1 2.2-.2v3.6c-.9.2-2.1.3-3.8.3-2.1 0-3.6-.4-4.6-1.2s-1.5-2.2-1.5-4.2v-16.8h-4.3v-3.4z"/><path d="m462.9 82.9c-.1 2.6.5 4.8 1.7 6.5 1.1 1.7 2.9 2.6 5.3 2.6 1.5 0 2.8-.4 3.9-1.3 1-.8 1.6-2.2 1.8-4h4.6c0 .6-.2 1.4-.4 2.3-.3 1-.8 2-1.7 3-.2.3-.6.6-1 1-.5.4-1 .7-1.7 1.1s-1.5.6-2.4.8c-.9.3-2 .4-3.3.4-7.6-.2-11.3-4.5-11.3-12.9 0-2.5.3-4.8 1-6.8s2-3.7 3.8-5.1c1.2-.8 2.4-1.3 3.7-1.6 1.3-.2 2.2-.3 3-.3 2.7 0 4.8.6 6.3 1.6s2.5 2.3 3.1 3.9c.6 1.5 1 3.1 1.1 4.6.1 1.6.1 2.9 0 4h-17.5m12.9-3c0-.3 0-.7 0-1.1s0-.8-.1-1.2c-.1-.9-.4-1.7-.8-2.5s-1-1.5-1.8-2c-.9-.5-2-.8-3.4-.8-.8 0-1.5.1-2.3.3s-1.5.7-2.2 1.3-1.2 1.3-1.6 2.3-.7 2.2-.8 3.6z"/><path d="m501.8 77.5c0-.3 0-.8-.1-1.4s-.3-1.1-.6-1.8c-.2-.6-.7-1.2-1.4-1.6s-1.6-.6-2.7-.6c-1.5 0-2.7.4-3.5 1.2-.9.8-1.5 1.7-1.9 2.8s-.6 2.2-.7 3.2c-.1 1.1-.2 1.8-.1 2.4 0 1.3.1 2.5.3 3.7s.5 2.3.9 3.3c.8 2 2.4 3 4.8 3.1 1.9 0 3.3-.7 4.1-1.9.8-1.1 1.2-2.3 1.2-3.6h4.6c-.2 2.5-1.1 4.6-2.7 6.3-1.7 1.8-4.1 2.7-7.1 2.7-.9 0-2.1-.2-3.6-.6-.7-.2-1.4-.6-2.2-1s-1.5-1-2.2-1.7c-.7-.9-1.4-2.1-2-3.6s-.9-3.5-.9-6.1.4-4.8 1.1-6.6c.7-1.7 1.6-3.1 2.7-4.2 1.1-1 2.3-1.8 3.6-2.2s2.5-.6 3.7-.6h1.6c.6.1 1.3.2 1.9.4.7.2 1.4.5 2.1 1 .7.4 1.3 1 1.8 1.7.9 1.1 1.4 2.1 1.7 3.1.2 1 .3 1.8.3 2.6z"/><path d="m509.3 69.4h4.3v-5.2l4.5-1.5v6.8h5.4v3.4h-5.4v15.1c0 .3 0 .6.1 1 0 .4.1.7.4 1.1.2.4.5.6 1 .8.4.3 1 .4 1.8.4 1 0 1.7-.1 2.2-.2v3.6c-.9.2-2.1.3-3.8.3-2.1 0-3.6-.4-4.6-1.2s-1.5-2.2-1.5-4.2v-16.8h-4.3v-3.4z"/><path d="m529.2 58.6h5.5v5.1h-5.5zm.5 10.9h4.6v25.1h-4.6z"/><path d="m541.8 82.4c0-1.6.2-3.2.6-4.8s1.1-3 2-4.4c1-1.3 2.2-2.4 3.8-3.2s3.6-1.2 5.9-1.2c2.4 0 4.5.4 6.1 1.3 1.5.9 2.7 2 3.6 3.3s1.5 2.8 1.8 4.3c.2.8.3 1.5.4 2.2v2.2c0 3.7-1 6.9-3 9.5s-5.1 4-9.3 4c-4-.1-7-1.4-9-3.9-1.9-2.5-2.9-5.6-2.9-9.3m4.7-.3c0 2.7.6 5 1.8 6.9 1.2 2 3 3 5.6 3.1.9 0 1.8-.2 2.7-.5.8-.3 1.6-.9 2.3-1.7s1.3-1.9 1.8-3.2c.4-1.3.6-2.9.6-4.7-.1-6.4-2.5-9.6-7.1-9.6-.7 0-1.5.1-2.4.3-.8.3-1.7.8-2.5 1.6-.8.7-1.4 1.7-1.9 3-.6 1.1-.9 2.8-.9 4.8z"/><path d="m574.3 72.4-.1-2.9h4.6v4.1c.2-.3.4-.8.7-1.2.3-.5.8-1 1.3-1.5.6-.5 1.4-1 2.3-1.3s2-.5 3.4-.5c.6 0 1.4.1 2.4.2.9.2 1.9.5 2.9 1.1s1.8 1.4 2.5 2.5c.6 1.2 1 2.7 1 4.7v17.1h-4.6v-16c0-.9-.1-1.7-.2-2.4-.2-.7-.5-1.3-1.1-1.9-1.2-1.1-2.6-1.7-4.3-1.7s-3.1.6-4.3 1.8c-1.3 1.2-2 3.1-2 5.7v14.5h-4.6z"/><path d="m14.8 108.5h5.2l14.1 36.1h-5.3l-3.8-9.4h-16.2l-3.8 9.4h-5zm-4.4 22.7h13.3l-6.5-17.8z"/><path d="m44.4 146.5c.1.7.2 1.4.4 1.9.2.6.5 1.1.9 1.6.8.9 2.3 1.4 4.4 1.5 1.6 0 2.8-.3 3.7-.9s1.5-1.4 1.9-2.4c.4-1.1.6-2.3.7-3.7s.1-2.9.1-4.6c-.5.9-1.1 1.7-1.8 2.3s-1.5 1-2.3 1.3c-1.7.4-3 .6-3.9.6-1.2 0-2.4-.2-3.8-.6s-2.6-1.2-3.7-2.5c-1-1.3-1.7-2.8-2.1-4.4s-.6-3.2-.6-4.8c0-4.3 1.1-7.4 3.2-9.5 2-2.1 4.6-3.1 7.6-3.1 1.3 0 2.3.1 3.2.4s1.6.6 2.1 1c.6.4 1.1.8 1.5 1.2.3.4.6.8.9 1.2v-3.4h4.4l-.1 4.5v15.7c0 2.9-.1 5.2-.2 6.7-.2 1.6-.5 2.8-1 3.7-1.1 1.9-2.6 3.2-4.6 3.7-1.9.6-3.8.8-5.6.8-2.4 0-4.3-.3-5.6-.8-1.4-.5-2.4-1.2-3-2s-1-1.7-1.2-2.7c-.2-.9-.3-1.8-.4-2.7zm5.3-5.8c1.4 0 2.5-.2 3.3-.7s1.5-1.1 2-1.8c.5-.6.9-1.4 1.2-2.5.3-1 .4-2.6.4-4.8 0-1.6-.2-2.9-.4-3.9-.3-1-.8-1.8-1.4-2.4-1.3-1.4-3-2.2-5.2-2.2-1.4 0-2.5.3-3.4 1s-1.6 1.5-2 2.4c-.4 1-.7 2-.9 3s-.2 2-.2 2.8c0 1 .1 1.9.3 2.9.2 1.1.5 2.1 1 3s1.2 1.6 2 2.2c.8.7 1.9 1 3.3 1z"/><path d="m73.3 132.9c-.1 2.6.5 4.8 1.7 6.5 1.1 1.7 2.9 2.6 5.3 2.6 1.5 0 2.8-.4 3.9-1.3 1-.8 1.6-2.2 1.8-4h4.6c0 .6-.2 1.4-.4 2.3-.3 1-.8 2-1.7 3-.2.3-.6.6-1 1-.5.4-1 .7-1.7 1.1s-1.5.6-2.4.8c-.9.3-2 .4-3.3.4-7.6-.2-11.3-4.5-11.3-12.9 0-2.5.3-4.8 1-6.8s2-3.7 3.8-5.1c1.2-.8 2.4-1.3 3.7-1.6 1.3-.2 2.2-.3 3-.3 2.7 0 4.8.6 6.3 1.6s2.5 2.3 3.1 3.9c.6 1.5 1 3.1 1.1 4.6.1 1.6.1 2.9 0 4h-17.5m12.9-3c0-.3 0-.7 0-1.1s0-.8-.1-1.2c-.1-.9-.4-1.7-.8-2.5s-1-1.5-1.8-2.1c-.9-.5-2-.8-3.4-.8-.8 0-1.5.1-2.3.3s-1.5.7-2.2 1.3-1.2 1.3-1.6 2.3-.7 2.2-.8 3.7z"/><path d="m98.6 122.4-.1-2.9h4.6v4.1c.2-.3.4-.8.7-1.2.3-.5.8-1 1.3-1.5.6-.5 1.4-1 2.3-1.3s2-.5 3.4-.5c.6 0 1.4.1 2.4.2.9.2 1.9.5 2.9 1.1s1.8 1.4 2.5 2.5c.6 1.2 1 2.7 1 4.7v17.1h-4.6v-16c0-.9-.1-1.7-.2-2.4-.2-.7-.5-1.3-1.1-1.9-1.2-1.1-2.6-1.7-4.3-1.7s-3.1.6-4.3 1.8c-1.3 1.2-2 3.1-2 5.7v14.5h-4.6z"/><path d="m142.7 127.5c0-.3 0-.8-.1-1.4s-.3-1.1-.6-1.8c-.2-.6-.7-1.2-1.4-1.6s-1.6-.6-2.7-.6c-1.5 0-2.7.4-3.5 1.2-.9.8-1.5 1.7-1.9 2.8s-.6 2.2-.7 3.2c-.1 1.1-.2 1.8-.1 2.4 0 1.3.1 2.5.3 3.7s.5 2.3.9 3.3c.8 2 2.4 3 4.8 3.1 1.9 0 3.3-.7 4.1-1.9.8-1.1 1.2-2.3 1.2-3.6h4.6c-.2 2.5-1.1 4.6-2.7 6.3-1.7 1.8-4.1 2.7-7.1 2.7-.9 0-2.1-.2-3.6-.6-.7-.2-1.4-.6-2.2-1s-1.5-1-2.2-1.7c-.7-.9-1.4-2.1-2-3.6s-.9-3.5-.9-6.1.4-4.8 1.1-6.6c.7-1.7 1.6-3.1 2.7-4.2 1.1-1 2.3-1.8 3.6-2.2s2.5-.6 3.7-.6h1.6c.6.1 1.3.2 1.9.4.7.2 1.4.5 2.1 1 .7.4 1.3 1 1.8 1.7.9 1.1 1.4 2.1 1.7 3.1.2 1 .3 1.8.3 2.6z"/><path d="m164.8 144.8-3.4 9.3h-4.7l3.8-9.6-10.3-25h5.2l7.6 19.8 7.7-19.8h5z"/></svg> </span> </a> <button type="button" class="usa-menu-btn usa-button--outline usa-button--inverse l-header__menu-button">Menu</button> </div> <div class="l-header__search" id="header-search-drawer"> <form class="usa-search usa-search--small usa-search--epa" method="get" action="https://search.epa.gov/epasearch"> <div role="search"> <label class="usa-search__label usa-sr-only" for="search-box">Search</label> <input class="usa-input" id="search-box" type="search" name="querytext" placeholder="Search EPA.gov"> <button class="button" type="submit" aria-label="Search"> <svg class="icon usa-search__submit-icon" aria-hidden="true"><use href="/themes/epa_theme/images/sprite.artifact.svg#magnifying-glass"></use></svg> <span class="usa-search__submit-text">Search</span> </button> <input type="hidden" name="areaname" value=""> <input type="hidden" name="areacontacts" value=""> <input type="hidden" name="areasearchurl" value=""> <input type="hidden" name="typeofsearch" value="epa"> <input type="hidden" name="result_template" value=""> </div> </form> </div> </div> </div> <div class="l-header__nav"> <nav class="usa-nav usa-nav--epa" role="navigation" aria-label="Primary navigation"> <div class="usa-nav__inner"> <button type="button" class="usa-nav__close" aria-label="Close"> <svg class="icon icon--nav-close" aria-hidden="true" role="img"><title>Primary navigation</title><use href="/themes/epa_theme/images/sprite.artifact.svg#xmark"></use></svg> </button> <div class="usa-nav__menu"> <ul class="menu menu--main menu--accordion usa-accordion"> <li class="menu__item has-subnav is-active-trail is-expanded"><button class="menu__link has-subnav is-active-trail is-expanded usa-nav__link usa-accordion__button" aria-expanded="false" type="button"> Environmental Topics <svg class="icon menu__link-icon" aria-hidden="true"><use href="/themes/epa_theme/images/sprite.artifact.svg#angle"></use></svg></button><ul class="menu menu__subnav usa-nav__submenu usa-megamenu is-wide"><li class="menu__item"><a href="/environmental-topics" class="menu__link" data-drupal-link-system-path="node/164839">Environmental Topics</a></li><li class="menu__item"><a href="/environmental-topics/air-topics" class="menu__link" data-drupal-link-system-path="node/165225">Air</a></li><li class="menu__item"><a href="/bedbugs" class="menu__link" data-drupal-link-system-path="node/17591">Bed Bugs</a></li><li class="menu__item"><a href="/environmental-topics/epa-efforts-reduce-exposure-carcinogens-and-prevent-cancer" class="menu__link" data-drupal-link-system-path="node/280190">Cancer</a></li><li class="menu__item"><a href="/environmental-topics/chemicals-pesticides-and-toxics-topics" class="menu__link" data-drupal-link-system-path="node/165371">Chemicals, Toxics, and Pesticide </a></li><li class="menu__item"><a href="/climate-change" class="menu__link" data-drupal-link-system-path="node/37925">Climate Change</a></li><li class="menu__item"><a href="/emergency-response" class="menu__link" data-drupal-link-system-path="node/18839">Emergency Response</a></li><li class="menu__item"><a href="/environmental-topics/environmental-information-by-location" class="menu__link" data-drupal-link-system-path="node/165443">Environmental Information by Location </a></li><li class="menu__item"><a href="/environmentaljustice" class="menu__link" data-drupal-link-system-path="node/66337">Environmental Justice</a></li><li class="menu__item"><a href="/environmental-topics/greener-living" class="menu__link" data-drupal-link-system-path="node/165399">Greener Living</a></li><li class="menu__item"><a href="/environmental-topics/health-topics" class="menu__link" data-drupal-link-system-path="node/165317">Health</a></li><li class="menu__item"><a href="/environmental-topics/land-waste-and-cleanup-topics" class="menu__link" data-drupal-link-system-path="node/165171">Land, Waste, and Cleanup</a></li><li class="menu__item"><a href="/lead" class="menu__link" data-drupal-link-system-path="node/3085">Lead</a></li><li class="menu__item"><a href="/mold" class="menu__link" data-drupal-link-system-path="node/37083">Mold</a></li><li class="menu__item"><a href="/radon" class="menu__link" data-drupal-link-system-path="node/38609">Radon</a></li><li class="menu__item"><a href="/research" class="menu__link" data-drupal-link-system-path="node/35507">Research</a></li><li class="menu__item is-active-trail"><a href="/environmental-topics/science-topics" class="menu__link is-active-trail is-active" aria-current="page" data-drupal-link-system-path="node/172685">Science Topics</a></li><li class="menu__item"><a href="/environmental-topics/water-topics" class="menu__link" data-drupal-link-system-path="node/164827">Water Topics</a></li><li class="menu__item"><a href="/topics-epa-web" class="menu__link" data-drupal-link-system-path="topics-epa-web">A-Z Topic Index</a></li></ul></li> <li class="menu__item has-subnav is-expanded"><button class="menu__link has-subnav is-expanded usa-nav__link usa-accordion__button" aria-expanded="false" type="button"> Laws & Regulations <svg class="icon menu__link-icon" aria-hidden="true"><use href="/themes/epa_theme/images/sprite.artifact.svg#angle"></use></svg></button><ul class="menu menu__subnav usa-nav__submenu usa-megamenu "><li class="menu__item"><a href="/laws-regulations" title="View links to regulatory information by topic and sector, and to top pages about environmental laws, regulations, policies, compliance, and enforcement" class="menu__link" data-drupal-link-system-path="node/3157">Laws & Regulations</a></li><li class="menu__item"><a href="/regulatory-information-sector" class="menu__link" data-drupal-link-system-path="node/3173">By Business Sector</a></li><li class="menu__item"><a href="/regulatory-information-topic" class="menu__link" data-drupal-link-system-path="node/66677">By Topic</a></li><li class="menu__item"><a href="/compliance" class="menu__link" data-drupal-link-system-path="node/19411">Compliance</a></li><li class="menu__item"><a href="/enforcement" class="menu__link" data-drupal-link-system-path="node/10885">Enforcement</a></li><li class="menu__item"><a href="/laws-regulations/laws-and-executive-orders" class="menu__link" data-drupal-link-system-path="node/66719">Laws and Executive Orders</a></li><li class="menu__item"><a href="/laws-regulations/regulations" class="menu__link" data-drupal-link-system-path="node/11249">Regulations</a></li></ul></li> <li class="menu__item has-subnav is-expanded"><button class="menu__link has-subnav is-expanded usa-nav__link usa-accordion__button" aria-expanded="false" type="button"> Report a Violation <svg class="icon menu__link-icon" aria-hidden="true"><use href="/themes/epa_theme/images/sprite.artifact.svg#angle"></use></svg></button><ul class="menu menu__subnav usa-nav__submenu usa-megamenu "><li class="menu__item"><a href="/report-violation" class="menu__link" data-drupal-link-system-path="node/271510">Report a Violation</a></li><li class="menu__item"><a href="https://echo.epa.gov/report-environmental-violations" class="menu__link">Environmental Violations</a></li><li class="menu__item"><a href="https://www.epaoig.gov/epa-oig-hotline-complaint-form" class="menu__link">Fraud, Waste or Abuse</a></li></ul></li> <li class="menu__item has-subnav is-expanded"><button class="menu__link has-subnav is-expanded usa-nav__link usa-accordion__button" aria-expanded="false" type="button"> About EPA <svg class="icon menu__link-icon" aria-hidden="true"><use href="/themes/epa_theme/images/sprite.artifact.svg#angle"></use></svg></button><ul class="menu menu__subnav usa-nav__submenu usa-megamenu "><li class="menu__item"><a href="/aboutepa" class="menu__link" data-drupal-link-system-path="node/851">About EPA</a></li><li class="menu__item"><a href="/aboutepa/our-mission-and-what-we-do" class="menu__link" data-drupal-link-system-path="node/2099">Our Mission and What We Do</a></li><li class="menu__item"><a href="/aboutepa/epa-administrator" class="menu__link" data-drupal-link-system-path="node/264813">EPA Administrator</a></li><li class="menu__item"><a href="/aboutepa#hq" class="menu__link" data-drupal-link-system-path="node/851">Headquarters Offices</a></li><li class="menu__item"><a href="/aboutepa/regional-and-geographic-offices" class="menu__link" data-drupal-link-system-path="node/254965">Regional Offices</a></li><li class="menu__item"><a href="/aboutepa/research-centers-programs-and-science-advisory-organizations" class="menu__link" data-drupal-link-system-path="node/254969">Labs and Research Centers</a></li><li class="menu__item"><a href="/planandbudget" class="menu__link" data-drupal-link-system-path="node/863">Planning, Budget, and Results</a></li><li class="menu__item"><a href="/aboutepa/epa-organization-chart" class="menu__link" data-drupal-link-system-path="node/2481">Organization Chart</a></li><li class="menu__item"><a href="/history" class="menu__link" data-drupal-link-system-path="node/162637">EPA History</a></li><li class="menu__item"><a href="https://cfpub.epa.gov/locator/index.cfm" class="menu__link">Staff Directory</a></li></ul></li> </ul> </div> </div> </nav> </div> </header> <main id="main" class="main" role="main" tabindex="-1"> <div class="l-page page-has-sidebar has-footer"> <div class="l-constrain"> <div class="l-page__header"> <div class="l-page__header-first"> <nav aria-labelledby="breadcrumb-label" class="breadcrumb" role="navigation"> <h2 id="breadcrumb-label" class="breadcrumb__title u-visually-hidden">Breadcrumb</h2> <ol class="breadcrumb__list"> <li class="breadcrumb__item"> <a class="breadcrumb__link" href="/">Home</a> </li> <li class="breadcrumb__item"> <a class="breadcrumb__link" href="/environmental-topics">Environmental Topics</a> </li> </ol> </nav> </div> </div> <div class="l-sidebar l-sidebar--reversed"> <div class="l-sidebar__main"> <article class="article" lang="en"> <h1 class="page-title"> Science Topics </h1> <div class="u-hide-for-print js-toggle-admin-content"> <div data-drupal-messages-fallback class="hidden"></div> </div> <div class="l-sidebar"> <div class="l-sidebar__main"> <div class="usa-summary-box" role="region"aria-labelledby="summary-box"> <div class="usa-summary-box__body"> <h2 class="usa-summary-box__heading" id="summary-box"> Summary </h2> <div class="usa-summary-box__text"> <figure class="figure figure--small u-align-left"> <div class="figure__media"> <img loading="eager" srcset="/system/files/styles/small/private/images/2022-08/julia-koblitz-RlOAwXt2fEA-unsplash_science.jpg?itok=2QPytW0A 320w, /system/files/styles/medium/private/images/2022-08/julia-koblitz-RlOAwXt2fEA-unsplash_science.jpg?itok=xQHHoXdD 640w" sizes="(max-width: 320px) calc(100vw - 2rem), 320px" width="320" height="213" src="/system/files/styles/small/private/images/2022-08/julia-koblitz-RlOAwXt2fEA-unsplash_science.jpg?itok=2QPytW0A" alt="Science Category"> </div> </figure> <p>EPA is one of the world’s leading environmental and human health research organizations. Science provides the foundation for Agency policies, actions, and decisions made on behalf of the American people. Learn more about <a data-entity-substitution="canonical" data-entity-type="node" data-entity-uuid="0f809f9e-3798-4d97-8adb-1e88851f501b" href="/research">research at EPA</a> and <a data-entity-substitution="canonical" data-entity-type="node" data-entity-uuid="09fa112f-7765-4563-95bc-68cfad4b0fa7" href="/measurements-modeling">environmental measurements and modeling</a>, and the wealth of <a data-entity-substitution="canonical" data-entity-type="node" data-entity-uuid="69859197-e85b-43b0-ab49-e3e5d8fd897a" href="/data">environmental data</a> shared by EPA.</p> </div> </div> </div> </div> <div class="l-sidebar__sidebar"> <div class="box box--related-info"> <h2 class="box__title">About EPA</h2> <div class="box__content"> <ul> <li><a href="/aboutepa/organization-chart-office-research-and-development-ord">Office of Research and Development (ORD)</a> </li> <li><a href="/aboutepa/research-centers-programs-and-science-advisory-organizations">EPA Laboratories, Research Centers, and Science Advisory</a></li> </ul> </div> </div> </div> </div> <div class="usa-section"> <div class="l-constrain"> <div class="l-grid l-grid--2-col l-column-layout"> <div> <div> </div> <h2>Science</h2> <ul> <li><a href="/participatory-science">Participatory Science for Environmental Protection</a></li> <li><a href="/climate-indicators">Climate Change Indicators</a></li> <li><a href="/measurements-modeling">Environmental Measurements and Modeling</a></li> <li><a href="/labs/laboratory-methods">Laboratory Methods</a></li> <li><a href="/risk">Risk Assessment</a></li> <li><a href="/scientific-integrity">Scientific Integrity</a></li> <li><a data-entity-substitution="canonical" data-entity-type="node" data-entity-uuid="67774880-97c4-4524-889a-09004a333e54" href="/sciencematters">Science Matters Newsletter</a></li> </ul> <h2>Data and Tools</h2> <ul> <li><a href="/air-sensor-toolbox">Air Sensor Toolbox</a></li> <li><a href="/comptox-tools/comptox-chemicals-dashboard">CompTox Chemicals Dashboard</a></li> <li><a href="/comptox-tools/ecotoxicology-ecotox-knowledgebase-resource-hub">Ecotoxicology Database (ECOTOX)</a></li> <li><a href="/enviroatlas">Enviro Atlas</a> </li> <li><a href="https://edg.epa.gov/metadata/catalog/main/home.page">Environmental Dataset Gateway</a></li> <li><a data-entity-substitution="canonical" data-entity-type="node" data-entity-uuid="69859197-e85b-43b0-ab49-e3e5d8fd897a" href="/data">EPA Open Data portal</a></li> <li><a href="/research/epa-science-models-and-research-tools-smart-search">EPA Science Models and Research Tools (SMaRT) Search</a></li> <li><a href="/expobox">ExpoBox (A Toolbox for Exposure Assessors)</a></li> <li><a href="/iris">Integrated Risk Information System</a></li> <li><a href="/report-environment">Report on the Environment: National Trend Data</a></li> <li><a href="/waterdata">Water Data and Tools</a></li> <li><a data-entity-substitution="canonical" data-entity-type="node" data-entity-uuid="19ac27f9-05a6-42e3-b5b7-1428bf3dc94c" href="/water-research/epanet">Water Research: EPANET</a></li> </ul> <h2 class="highlight">Latest Science Matters Articles</h2> <div data-embed-button="paragraphs" data-entity-label="Paragraphs" data-paragraph-id="05235527-c600-47b5-956c-6ee50db396ef" data-paragraph-revision-id="1676" data-langcode="en" data-view-mode="embed" data-entity-embed-display="entity_reference_revisions:entity_reference_revisions_entity_view" data-entity-type="embedded_paragraphs" data-entity-uuid="05235527-c600-47b5-956c-6ee50db396ef" data-entity-embed-display-settings="[]" class="embedded-entity"> <div class="view view--dynamic-content-list view--display-block_1 js-view-dom-id-bab2c8cbe32ab4e46d04284f3276efe3348dff01b3a6825c8f4be1ad47862306 margin-bottom-4"> <ul class="usa-collection"> <li class="usa-collection__item"> <div class="usa-collection__body" lang="en"> <h3 class="usa-collection__heading"> <a class="usa-link" href="/sciencematters/meet-epa-research-limnologist-dr-ryan-lepak"> Meet EPA Research Limnologist Dr. Ryan Lepak </a> </h3> <p class="usa-collection__description"> EPA Researcher Dr. Ryan Lepak focuses on understanding pathways of PFAS and mercury exposure in fish across the Great Lakes. Using historical fish archives, Ryan and the team construct timelines of PFAS and mercury exposure to analyze lakes’ responsiveness </p> </div> </li> <li class="usa-collection__item"> <div class="usa-collection__body" lang="en"> <h3 class="usa-collection__heading"> <a class="usa-link" href="/sciencematters/epa-releases-seqapass-version-8"> EPA Releases SeqAPASS Version 8 </a> </h3> <p class="usa-collection__description"> EPA released the 8th version of Sequence Alignment to Predict Across Species Susceptibility (SeqAPASS). SeqAPASS is an online screening tool that allows users to rapidly extrapolate toxicity information across animal species. </p> </div> </li> <li class="usa-collection__item"> <div class="usa-collection__body" lang="en"> <h3 class="usa-collection__heading"> <a class="usa-link" href="/sciencematters/aaas-and-aspph-fellows-epa"> AAAS and ASPPH Fellows at EPA </a> </h3> <p class="usa-collection__description"> EPA holds cooperative agreements with professional organizations to sponsor fellowship programs. Several current and past participants of these fellowship programs shared their experiences and accomplishments from their time at the agency. </p> </div> </li> </ul> </div> </div> <p><a class="usa-button" data-entity-substitution="canonical" data-entity-type="node" data-entity-uuid="67774880-97c4-4524-889a-09004a333e54" href="/sciencematters">Read more from Science Matters</a></p> </div> <div> <div> </div> <h2>Research</h2> <ul> <li><a href="https://hero.epa.gov/hero/index.cfm">HERO: Health and Environmental Research Online</a></li> <li><a href="/innovation">Innovation at EPA</a></li> <li><a href="/chemical-research/epa-new-approach-methods-efforts-reduce-use-vertebrate-animals-chemical-testing">Reducing Animal Testing at EPA</a></li> <li><a href="/research">Research at EPA</a></li> <li><a href="https://cfpub.epa.gov/si/">Science Inventory</a></li> </ul> <h2>Grants and Opportunities</h2> <ul> <li><a href="/research-grants">Research Grants</a></li> <li><a href="/careers/science-careers-epa">Science Careers at EPA</a></li> <li><a href="/sbir">Small Business Innovation Research Grants</a></li> <li><a href="/grants">Understanding, Managing, and Applying for EPA Grants</a></li> </ul> </div> </div> </div> </div> </article> </div> <div class="l-sidebar__sidebar"> <div class="menu-sidenav__overlay"></div> <div id="block-webareamenu" class="block--web-area-menu block"> <h2 class="block__title"><a href="/environmental-topics" hreflang="en">Environmental Topics</a></h2> <div class="block__content"> <button type="button" class="usa-button usa-button--outline web-area-menu__button" id="web-area-menu__button" aria-label="toggle the side navigation menu"> <svg class="usa-icon menu-button--open" aria-hidden="true" role="img"><title>Open Sidenav Menu</title><use href="/themes/epa_theme/images/sprite.svg#menu"></use></svg> <svg class="usa-icon menu-button--close" aria-hidden="true" role="img"><title>Close Sidenav Menu</title><use href="/themes/epa_theme/images/sprite.svg#close"></use></svg> </button> <nav class="menu--sidenav-nav"> <ul class="menu--sidenav menu menu--group_menu_link_content-576"> <li class="menu__item"><a href="/environmental-topics/air-topics" class="menu__link" data-drupal-link-system-path="node/165225">Air Topics</a></li> <li class="menu__item"><a href="/environmental-topics/epa-efforts-reduce-exposure-carcinogens-and-prevent-cancer" class="menu__link" data-drupal-link-system-path="node/280190">Cancer</a></li> <li class="menu__item"><a href="/environmental-topics/chemicals-pesticides-and-toxics-topics" class="menu__link" data-drupal-link-system-path="node/165371">Chemicals, Pesticides, and Toxics Topics</a></li> <li class="menu__item"><a href="/environmental-topics/environmental-information-by-location" class="menu__link" data-drupal-link-system-path="node/165443">Environmental Information by Location</a></li> <li class="menu__item"><a href="/environmental-topics/greener-living" class="menu__link" data-drupal-link-system-path="node/165399">Greener Living</a></li> <li class="menu__item"><a href="/environmental-topics/health-topics" class="menu__link" data-drupal-link-system-path="node/165317">Health Topics</a></li> <li class="menu__item"><a href="/environmental-topics/land-waste-and-cleanup-topics" class="menu__link" data-drupal-link-system-path="node/165171">Land, Waste, and Cleanup Topics</a></li> <li class="menu__item is-active-trail"><a href="/environmental-topics/science-topics" class="menu__link is-active-trail is-active" aria-current="page" data-drupal-link-system-path="node/172685">Science Topics</a></li> <li class="menu__item"><a href="/environmental-topics/water-topics" class="menu__link" data-drupal-link-system-path="node/164827">Water Topics</a></li> </ul> </nav> </div> </div> <div class="menu-sidenav__contact" id="menu-sidenav__contact"> <a href="/environmental-topics/forms/contact-us" hreflang="en">Contact Us</a> </div> </div> </div> </div> <div class="l-page__footer"> <div class="l-constrain"> <div class="l-page__footer-contact"><a href="/environmental-topics/forms/contact-us">Contact Us</a> to ask a question, provide feedback, or report a problem.</div> <div class="l-page__footer-last-updated">Last updated on December 14, 2023</div> </div> </div> </div> </main> <footer class="footer" role="contentinfo"> <div class="l-constrain"> <div class="footer__pre-footer"> <ul class="list list--footer-language-bar"> <li><a href="/lep/assistance">Assistance</a></li> <li><a href="/lep/assistance#esp">Ayuda</a></li> <li><a href="/lep/assistance#ar">مساعدة</a></li> <li><a href="/lep/assistance#chi-s">帮助 (简体版)</a></li> <li><a href="/lep/assistance#chi-tr">幫助 (繁體版)</a></li> <li><a href="/lep/assistance#fr">Aide</a></li> <li><a href="/lep/assistance#hc">Asistans</a></li> <li><a href="/lep/assistance#kor">지원</a></li> <li><a href="/lep/assistance#port">Assistência</a></li> <li><a href="/lep/assistance#rus">Помощь</a></li> <li><a href="/lep/assistance#tag">Tulong</a></li> <li><a href="/lep/assistance#viet">Trợ Giúp</a></li> </ul> </div> <img class="footer__epa-seal" src="/themes/epa_theme/images/epa-seal.svg" alt="United States Environmental Protection Agency" height="100" width="100"> <div class="footer__content contextual-region"> <div class="footer__column"> <h2>Discover.</h2> <ul class="menu menu--footer"> <li class="menu__item"> <a href="/accessibility/epa-accessibility-statement" class="menu__link">Accessibility Statement</a> </li>  <li class="menu__item"> <a href="/planandbudget" class="menu__link">Budget & Performance</a> </li> <li class="menu__item"> <a href="/contracts" class="menu__link">Contracting</a> </li> <li class="menu__item"> <a href="/utilities/wwwepagov-snapshots" class="menu__link">EPA www Web Snapshot</a> </li> <li class="menu__item"> <a href="/grants" class="menu__link">Grants</a> </li> <li class="menu__item"> <a href="/ocr/no-fear-act-data" class="menu__link">No FEAR Act Data</a> </li> <li class="menu__item"> <a href="/web-policies-and-procedures/plain-writing" class="menu__link">Plain Writing</a> </li> <li class="menu__item"> <a href="/privacy" class="menu__link">Privacy</a> </li> <li class="menu__item"> <a href="/privacy/privacy-and-security-notice" class="menu__link">Privacy and Security Notice</a> </li> </ul> </div> <div class="footer__column"> <h2>Connect.</h2> <ul class="menu menu--footer"> <li class="menu__item"> <a href="/data" class="menu__link">Data</a> </li> <li class="menu__item"> <a href="https://www.epaoig.gov/" class="menu__link">Inspector General</a> </li> <li class="menu__item"> <a href="/careers" class="menu__link">Jobs</a> </li> <li class="menu__item"> <a href="/newsroom" class="menu__link">Newsroom</a> </li> <li class="menu__item"> <a href="https://www.regulations.gov/" class="menu__link">Regulations.gov</a> </li> <li class="menu__item"> <a href="/newsroom/email-subscriptions-epa-news-releases" class="menu__link">Subscribe</a> </li> <li class="menu__item"> <a href="https://www.usa.gov/" class="menu__link">USA.gov</a> </li> <li class="menu__item"> <a href="https://www.whitehouse.gov/" class="menu__link">White House</a> </li> </ul> </div> <div class="footer__column"> <h2>Ask.</h2> <ul class="menu menu--footer"> <li class="menu__item"> <a href="/home/forms/contact-epa" class="menu__link">Contact EPA</a> </li> <li class="menu__item"> <a href="/web-policies-and-procedures/epa-disclaimers" class="menu__link">EPA Disclaimers</a> </li> <li class="menu__item"> <a href="/aboutepa/epa-hotlines" class="menu__link">Hotlines</a> </li> <li class="menu__item"> <a href="/foia" class="menu__link">FOIA Requests</a> </li> <li class="menu__item"> <a href="/home/frequent-questions-specific-epa-programstopics" class="menu__link">Frequent Questions</a> </li> </ul> <h2>Follow.</h2> <ul class="menu menu--social"> <li class="menu__item"> <a class="menu__link" aria-label="EPA’s Facebook" href="https://www.facebook.com/EPA"> <svg class="icon icon--social" aria-hidden="true"> <use xlink:href="/themes/epa_theme/images/sprite.artifact.svg#facebook-square" xmlns:xlink="http://www.w3.org/1999/xlink" /> </svg> </a> </li> <li class="menu__item"> <a class="menu__link" aria-label="EPA’s Twitter / X" href="https://x.com/epa"> <svg class="icon icon--social" aria-hidden="true"> <use xlink:href="/themes/epa_theme/images/sprite.artifact.svg#twitter-square" xmlns:xlink="http://www.w3.org/1999/xlink" /> </svg> </a> </li> <li class="menu__item"> <a class="menu__link" aria-label="EPA’s Youtube" href="https://www.youtube.com/user/USEPAgov"> <svg class="icon icon--social" aria-hidden="true"> <use xlink:href="/themes/epa_theme/images/sprite.artifact.svg#youtube-square" xmlns:xlink="http://www.w3.org/1999/xlink" /> </svg> </a> </li> <li class="menu__item"> <a class="menu__link" aria-label="EPA’s Flickr" href="https://www.flickr.com/photos/usepagov"> <svg class="icon icon--social" aria-hidden="true"> <use xlink:href="/themes/epa_theme/images/sprite.artifact.svg#flickr-square" xmlns:xlink="http://www.w3.org/1999/xlink" /> </svg> </a> </li> <li class="menu__item"> <a class="menu__link" aria-label="EPA’s Instagram" href="https://www.instagram.com/epagov"> <svg class="icon icon--social" aria-hidden="true"> <use xlink:href="/themes/epa_theme/images/sprite.artifact.svg#instagram-square" xmlns:xlink="http://www.w3.org/1999/xlink" /> </svg> </a> </li> </ul> </div> </div> </div> </footer> </div> <a href="#top" class="back-to-top" title="Back to top"> <svg class="back-to-top__icon" role="img" aria-label="Back to top"> <use href="/themes/epa_theme/images/sprite.artifact.svg#angle"></use> </svg> </a> <script type="application/json" data-drupal-selector="drupal-settings-json">{"path":{"baseUrl":"\/","pathPrefix":"","currentPath":"node\/172685","currentPathIsAdmin":false,"isFront":false,"currentLanguage":"en"},"pluralDelimiter":"\u0003","suppressDeprecationErrors":true,"ajaxPageState":{"libraries":"eJxVzVEKwyAQBNALWfdIstZpsq0acTXW27cEQtOfYXgwDHKTNh2SR6A7lyZbNijs2ooEWuLmOV4gIQi7KPl1QZWAzLtLyP3gMVXGXOjbbxnDHCt6SGyo9nwpXHmpXFalUHvhaH9iey7dR9EVwejUhkSeFWYXDKUjLT_5_QdpCz3iA_mnUhw","theme":"epa_theme","theme_token":null},"ajaxTrustedUrl":[],"viewsAjaxGet":{"public_alerts":"public_alerts"},"epaAlerts":{"context":"public"},"mediaelement":{"attachSitewide":0},"views":{"ajax_path":"\/views\/ajax","ajaxViews":{"views_dom_id:bab2c8cbe32ab4e46d04284f3276efe3348dff01b3a6825c8f4be1ad47862306":{"view_name":"dynamic_content_list","view_display_id":"block_1","view_args":"","view_path":"\/node\/172685","view_base_path":null,"view_dom_id":"bab2c8cbe32ab4e46d04284f3276efe3348dff01b3a6825c8f4be1ad47862306","pager_element":0,"viewsreference":{"data":{"epa_view_mode":"teaser","epa_pager":0,"pager":null,"limit":"3","title":null,"argument":null,"offset":null,"exposed_filters":{"vr_exposed_filters_visible":false,"type":[],"title_wrapper":{"title_op":"contains","title":""},"gid":"Science Matters (45061)","field_channel_target_id":[],"field_type_target_id":[],"field_description_value":"","field_keywords_target_id":"","field_last_published_value":"","field_env_laws_regs_and_treaties_target_id":[],"field_geographic_locations_target_id":[],"field_language_value":{"en":"en"}},"exposed_sorts":{"sort_by":"created_1","sort_order":"DESC"}},"enabled_settings":{"no_results_text":"no_results_text","epa_pager":"epa_pager","epa_view_mode":"epa_view_mode","limit":"limit","exposed_filters":"exposed_filters","exposed_sorts":"exposed_sorts"},"parent_entity_type":"paragraph","parent_entity_id":"1107812","parent_field_name":"field_views_reference"}}}},"user":{"uid":0,"permissionsHash":"1bc7b971ae8e07374eacb42449a528f4db7bd5756e5e09990fbb0d99517cc1e9"}}</script> <script src="/core/assets/vendor/jquery/jquery.min.js?v=3.7.1"></script> <script src="/core/assets/vendor/once/once.min.js?v=1.0.1"></script> <script src="/core/misc/drupalSettingsLoader.js?v=10.2.3"></script> <script src="/core/misc/drupal.js?v=10.2.3"></script> <script src="/core/misc/drupal.init.js?v=10.2.3"></script> <script src="/core/assets/vendor/tabbable/index.umd.min.js?v=6.2.0"></script> <script src="/modules/custom/epa_wysiwyg/js/plugins/epaNew/epaNew.js?snbziw"></script> <script src="/core/misc/progress.js?v=10.2.3"></script> <script src="/core/assets/vendor/loadjs/loadjs.min.js?v=4.2.0"></script> <script src="/core/misc/debounce.js?v=10.2.3"></script> <script src="/core/misc/announce.js?v=10.2.3"></script> <script src="/core/misc/message.js?v=10.2.3"></script> <script src="/core/misc/ajax.js?v=10.2.3"></script> <script src="/themes/contrib/stable/js/ajax.js?v=10.2.3"></script> <script src="/themes/epa_theme/js/dist/common.min.js?v=20240924"></script> <script src="/themes/epa_theme/js/dist/scripts.min.js?v=20240924"></script> <script src="/themes/epa_theme/js/dist/header-search.min.js?v=20240924"></script> <script src="/themes/epa_theme/js/dist/epa-alerts.min.js?v=20240924"></script> <script src="/themes/epa_theme/js/dist/sitewide-alert.min.js?v=20240924"></script> <script src="/themes/epa_theme/js/dist/private-sitewide-alert.min.js?v=20240924"></script> <script src="/themes/epa_theme/js/dist/definition.min.js?v=20240924"></script> <script src="/themes/epa_theme/js/dist/external-links.min.js?v=20240924"></script> <script src="/themes/epa_theme/js/dist/protected-links.min.js?v=20240924"></script> <script src="/themes/epa_theme/js/dist/vid-copy.min.js?v=20240924"></script> <script src="/themes/epa_theme/js/dist/sidenav-menu.min.js?v=20240924"></script> <script src="/themes/epa_theme/js/dist/media-link.min.js?v=20240924"></script> <script src="/core/assets/vendor/jquery-form/jquery.form.min.js?v=4.3.0"></script> <script src="/core/modules/views/js/base.js?v=10.2.3"></script> <script src="/core/modules/views/js/ajax_view.js?v=10.2.3"></script> <style> h2.usa-summary-box__heading { display: none; } </style> </body> </html>

CINXE.COM

Science Topics | US EPA