Chemical Dumping Linked to California Sea Lions’ High Cancer Rates

California sea lions (Zalophus californianus) have one of the highest rates of cancer of all mammals, and scientists have long wondered why.
The answer, published in Frontiers in Marine Science in December 2020, is complex. But a key component is exposure to toxic chemicals, from when the California coast was an industrial dumping ground.
"It is extraordinary, the level of pollutants in these animals in California. It is a big factor in why we're seeing this level of cancer," study coauthor and Marine Mammal Center pathologist Dr. Pádraig Duignan told the Los Angeles Times.
In the past 40 years, 18 to 23 percent of the sea lions treated at the Marine Mammal Center hospital in Sausalito, California died of a particular type of cancer, the center wrote in a press release. This is unusual, as wild mammals tend not to develop this disease. In fact, the California sea lions have the highest rate of a single type of cancer of any mammal, including humans.
This shocked study lead author Frances Gulland when she first started to work at the Marine Mammal Center 26 years ago.
"Wildlife should not be getting cancer like this, that's crazy!" Gulland told the Los Angeles Times. "How can that be?"
But the 250,000 or so California sea lions breed on islands off the Central California coast, the study authors noted. This is the same area that saw dumping of DDT in the 1960s, and pollution from industrialization and urbanization in the following decades. Industrial trash, radioactive material and waste from oil refineries was also dumped into the ocean, the Los Angeles Times reported.
"With all the dumping since the Second World War, right up to the 1970s, that's a lot of stuff out there," Duignan told the Los Angeles Times. "These legacy chemicals haven't broken down anything appreciable in intervening years, and nobody knows if they ever will. This is something that they're going to have to be exposed to for who knows how long."
To find out if the chemical dumping was to blame for the cancer, researchers examined 394 dead sea lions over a more than 20-year period. They found that the sea lions were infected with a herpes virus that was partly responsible for triggering the cancer. At the same time, the sea lions with higher concentrations of DDT, PCBs and other toxic chemicals in their blubber were more likely to see the cancer spread.
What's more, the sea lions in the study had some of the highest concentrations of organic pollutants in their blubber of any marine mammal, the press release noted.
The results show the dangers that toxins can pose to wildlife long after they are phased out of use. They also have troubling implications for human health.
"Even though some of the pollutants we're finding in the blubber have been out of use for years, these cancer-causing elements remain in the environment for a very long time and wreak havoc on opportunistic coastal feeders like sea lions," Duignan said in the press release. "It concerns me knowing that we consume very similar seafood as these cancer victims and that the ocean is raising a loud and clear alarm in the sick bodies of a sentinel species."
Gulland agreed.
"While there is more to be learned about the complex factors that play into the development of this disease, what we learn from these animals contributes to research that underpins the threat to human health from pollutants in the ocean," she said in the press release.
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Wisdom the mōlī, or Laysan albatross, is the oldest wild bird known to science at the age of at least 70. She is also, as of February 1, a new mother.
<div id="dadb2" class="rm-shortcode" data-rm-shortcode-id="aa2ad8cb566c9b4b6d2df2693669f6f9"><blockquote class="twitter-tweet twitter-custom-tweet" data-twitter-tweet-id="1357796504740761602" data-partner="rebelmouse"><div style="margin:1em 0">🚨Cute baby alert! Wisdom's chick has hatched!!! 🐣😍 Wisdom, a mōlī (Laysan albatross) and world’s oldest known, ban… https://t.co/Nco050ztBA</div> — USFWS Pacific Region (@USFWS Pacific Region)<a href="https://twitter.com/USFWSPacific/statuses/1357796504740761602">1612558888.0</a></blockquote></div>
The Science Behind Frozen Wind Turbines – and How to Keep Them Spinning Through the Winter
By Hui Hu
Winter is supposed to be the best season for wind power – the winds are stronger, and since air density increases as the temperature drops, more force is pushing on the blades. But winter also comes with a problem: freezing weather.
Comparing rime ice and glaze ice shows how each changes the texture of the blade. Gao, Liu and Hu, 2021, CC BY-ND
Ice buildup changes air flow around the turbine blade, which can slow it down. The top photos show ice forming after 10 minutes at different temperatures in the Wind Research Tunnel. The lower measurements show airflow separation as ice accumulates. Icing Research Tunnel of Iowa State University, CC BY-ND
How ice builds up on the tips of turbine blades. Gao, Liu and Hu, 2021, CC BY-ND
While traditional investment in the ocean technology sector has been tentative, growth in Israeli maritime innovations has been exponential in the last few years, and environmental concern has come to the forefront.
theDOCK aims to innovate the Israeli maritime sector. Pexels
<p>The UN hopes that new investments in ocean science and technology will help turn the tide for the oceans. As such, this year kicked off the <a href="https://www.oceandecade.org/" target="_blank" rel="noopener noreferrer">United Nations Decade of Ocean Science for Sustainable Development (2021-2030)</a> to galvanize massive support for the blue economy.</p><p>According to the World Bank, the blue economy is the "sustainable use of ocean resources for economic growth, improved livelihoods, and jobs while preserving the health of ocean ecosystem," <a href="https://www.sciencedirect.com/science/article/pii/S0160412019338255#b0245" target="_blank" rel="noopener noreferrer">Science Direct</a> reported. It represents this new sector for investments and innovations that work in tandem with the oceans rather than in exploitation of them.</p><p>As recently as Aug. 2020, <a href="https://www.reutersevents.com/sustainability/esg-investors-slow-make-waves-25tn-ocean-economy" target="_blank" rel="noopener noreferrer">Reuters</a> noted that ESG Investors, those looking to invest in opportunities that have a positive impact in environmental, social and governance (ESG) issues, have been interested in "blue finance" but slow to invest.</p><p>"It is a hugely under-invested economic opportunity that is crucial to the way we have to address living on one planet," Simon Dent, director of blue investments at Mirova Natural Capital, told Reuters.</p><p>Even with slow investment, the blue economy is still expected to expand at twice the rate of the mainstream economy by 2030, Reuters reported. It already contributes $2.5tn a year in economic output, the report noted.</p><p>Current, upward <a href="https://www.ecowatch.com/-innovation-blue-economy-2646147405.html" target="_self">shifts in blue economy investments are being driven by innovation</a>, a trend the UN hopes will continue globally for the benefit of all oceans and people.</p><p>In Israel, this push has successfully translated into investment in and innovation of global ports, shipping, logistics and offshore sectors. The "Startup Nation," as Israel is often called, has seen its maritime tech ecosystem grow "significantly" in recent years and expects that growth to "accelerate dramatically," <a href="https://itrade.gov.il/belgium-english/how-israel-is-becoming-a-port-of-call-for-maritime-innovation/" target="_blank" rel="noopener noreferrer">iTrade</a> reported.</p><p>Driving this wave of momentum has been rising Israeli venture capital hub <a href="https://www.thedockinnovation.com/" target="_blank" rel="noopener noreferrer">theDOCK</a>. Founded by Israeli Navy veterans in 2017, theDOCK works with early-stage companies in the maritime space to bring their solutions to market. The hub's pioneering efforts ignited Israel's maritime technology sector, and now, with their new fund, theDOCK is motivating these high-tech solutions to also address ESG criteria.</p><p>"While ESG has always been on theDOCK's agenda, this theme has become even more of a priority," Nir Gartzman, theDOCK's managing partner, told EcoWatch. "80 percent of the startups in our portfolio (for theDOCK's Navigator II fund) will have a primary or secondary contribution to environmental, social and governance (ESG) criteria."</p><p>In a company presentation, theDOCK called contribution to the ESG agenda a "hot discussion topic" for traditional players in the space and their boards, many of whom are looking to adopt new technologies with a positive impact on the planet. The focus is on reducing carbon emissions and protecting the environment, the presentation outlines. As such, theDOCK also explicitly screens candidate investments by ESG criteria as well.</p><p>Within the maritime space, environmental innovations could include measures like increased fuel and energy efficiency, better monitoring of potential pollution sources, improved waste and air emissions management and processing of marine debris/trash into reusable materials, theDOCK's presentation noted.</p>theDOCK team includes (left to right) Michal Hendel-Sufa, Head of Alliances, Noa Schuman, CMO, Nir Gartzman, Co-Founder & Managing Partner, and Hannan Carmeli, Co-Founder & Managing Partner. Dudu Koren
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