03/06/09

Arsenic exposure may decrease immunity to flu

Millions of people are exposed to arsenic levels in drinking water that exceed guideline values Copyright: FAO photo

By: T.V. Padma

We encourage you to republish this article online and in print, it’s free under our creative commons attribution license, but please follow some simple guidelines:

You have to credit our authors.
You have to credit SciDev.Net — where possible include our logo with a link back to the original article.
You can simply run the first few lines of the article and then add: “Read the full article on SciDev.Net” containing a link back to the original article.
If you want to also take images published in this story you will need to confirm with the original source if you're licensed to use them.
The easiest way to get the article on your site is to embed the code below.

For more information view our media page and republishing guidelines.

The full article is available here as HTML.

Press Ctrl-C to copy

<div class="article-wrap">
<div id="article-introduction">
<h1>Arsenic exposure may decrease immunity to flu</h1>
<h4>By: T.V. Padma</h4>
</div>
<br />
<br />

<div id="article-body">
<p>[NEW DELHI] <span>Drinking water contaminated with low doses of arsenic reduces immunity to influenza, new research suggests.</span></p>
<p><span>In a US-based study, mice were given drinking water containing 100 parts per billion of arsenic for five weeks before being exposed to the influenza A (H1N1) virus </span>—<span> the influenza subtype that includes swine flu. When researchers then measured the animals’ immune response to infection, it was found to be significantly weakened when compared with that of mice in a control group.</span></p>
<p><span>The findings were published online last month (May) in <em>Environment Health Perspectives</em>. </span></p>
<p><span>Arsenic is widely distributed throughout the earth’s crust and hundreds of millions of people are exposed to levels in drinking water that exceed guideline values (set at ten parts per billion by the US Environmental Protection Agency). Countries affected include numerous developing countries, Australia and the United States.</span></p>
<p>Joshua Hamilton, co-author of the study and <span>chief academic and scientific officer at the Marine Biology Laboratory in Massachusetts, United States, explains in a press release that under normal conditions a human or mouse exposed to the flu would develop an immediate immune response. </span></p>
<p><span>But the mice in his study showed a response that was initially feeble and then, a few days later, when a response finally kicked in, too robust and too late.</span></p>
<p><span>Writing in EHP, the study’s researchers say </span><span>the impact of arsenic exposure on the potential for a pandemic flu outbreak is of particular concern, given that many of the areas with confirmed human cases of avian and swine flu are known to include populations that are exposed to significant levels of arsenic </span>— such as Mexico and parts of South-East Asia.</p>
<div>
<p><span>But Hamilton believes the negative effects of arsenic exposure are not limited to people exposed to the flu, or even viruses.</span></p>
<p><span>"We believe there is a general suppression of innate immunity," he told SciDev.Net. "…our results on the effects of arsenic on the immune system argue this would lead to problems with virtually any immune challenge."</span></p>
</div>
<p><span>Scientists from the International Centre for Diarrhoeal Disease Research (ICDDR) based in Bangladesh, a country with high levels of arsenic contamination of ground water, say that at this stage the direct link between arsenic and H1N1 susceptibility is "speculative".</span></p>
<p>But according to Stephen Luby, head of ICDDR’s programme on infectious diseases and vaccine sciences, the US study has generated important ideas and draws attention to the health effects of being exposed to arsenic.</p>
<p><span><a href="http://www.ehponline.org/members/2009/0900911/0900911.pdf"><span>Link to full paper in <em>Environment Health Perspectives</em></span></a> <img decoding="async" data-src="http://c96267.r67.cf3.rackcdn.com/icon_pdf-transparent.png" alt="" src="data:image/gif;base64,R0lGODlhAQABAAAAACH5BAEKAAEALAAAAAABAAEAAAICTAEAOw==" class="lazyload" /><noscript><img decoding="async" data-src="http://c96267.r67.cf3.rackcdn.com/icon_pdf-transparent.png" alt="" src="data:image/gif;base64,R0lGODlhAQABAAAAACH5BAEKAAEALAAAAAABAAEAAAICTAEAOw==" class="lazyload" /><noscript><img decoding="async" src="http://c96267.r67.cf3.rackcdn.com/icon_pdf-transparent.png" alt="" /></noscript></noscript>[490KB]</span></p>

</div>
<div class="quick-links-wrapper">
<h3>You might also like</h3>
[related-articles]
</div>
<p>This article was originally published on <a href="https://www.scidev.net" target="_blank">SciDev.Net</a>. Read the <a href="https://www.scidev.net/global/news/arsenic-exposure-may-decrease-immunity-to-flu/" target="_blank">original article</a>.</p>
<script type="text/javascript">
(function(e,t,n,r,i,s,o){e["GoogleAnalyticsObject"]=i;e[i]=e[i]||function(){(e[i].q=e[i].q||[]).push(arguments)},e[i].l=1*new Date;s=t.createElement(n),o=t.getElementsByTagName(n)[0];s.async=1;s.src=r;o.parentNode.insertBefore(s,o)})(window,document,"script","//www.google-analytics.com/ga.js","ga");var _gaq=_gaq||[];var _gaq=_gaq||[];_gaq.push(["_setAccount","UA-3223906-8"],["_trackEvent","article interaction","republished","https://www.scidev.net/global/news/arsenic-exposure-may-decrease-immunity-to-flu/",null,true])
</script>
</div>

[NEW DELHI] Drinking water contaminated with low doses of arsenic reduces immunity to influenza, new research suggests.

In a US-based study, mice were given drinking water containing 100 parts per billion of arsenic for five weeks before being exposed to the influenza A (H1N1) virus — the influenza subtype that includes swine flu. When researchers then measured the animals’ immune response to infection, it was found to be significantly weakened when compared with that of mice in a control group.

The findings were published online last month (May) in Environment Health Perspectives.

Arsenic is widely distributed throughout the earth’s crust and hundreds of millions of people are exposed to levels in drinking water that exceed guideline values (set at ten parts per billion by the US Environmental Protection Agency). Countries affected include numerous developing countries, Australia and the United States.

Joshua Hamilton, co-author of the study and chief academic and scientific officer at the Marine Biology Laboratory in Massachusetts, United States, explains in a press release that under normal conditions a human or mouse exposed to the flu would develop an immediate immune response.

But the mice in his study showed a response that was initially feeble and then, a few days later, when a response finally kicked in, too robust and too late.

Writing in EHP, the study’s researchers say the impact of arsenic exposure on the potential for a pandemic flu outbreak is of particular concern, given that many of the areas with confirmed human cases of avian and swine flu are known to include populations that are exposed to significant levels of arsenic — such as Mexico and parts of South-East Asia.

But Hamilton believes the negative effects of arsenic exposure are not limited to people exposed to the flu, or even viruses.

"We believe there is a general suppression of innate immunity," he told SciDev.Net. "…our results on the effects of arsenic on the immune system argue this would lead to problems with virtually any immune challenge."

Scientists from the International Centre for Diarrhoeal Disease Research (ICDDR) based in Bangladesh, a country with high levels of arsenic contamination of ground water, say that at this stage the direct link between arsenic and H1N1 susceptibility is "speculative".

But according to Stephen Luby, head of ICDDR’s programme on infectious diseases and vaccine sciences, the US study has generated important ideas and draws attention to the health effects of being exposed to arsenic.

Link to full paper in Environment Health Perspectives [490KB]