Navigation Links
EPA should pursue cumulative risk assessment of phthalates and other chemicals
Date:12/18/2008

WASHINGTON -- The U.S. Environmental Protection Agency should examine whether combined exposures to chemicals known as phthalates could cause adverse health effects in humans, says a new report from the National Research Council. In addition, this analysis, called a cumulative risk assessment, should consider other chemicals that could potentially cause the same health effects as phthalates, instead of focusing on chemicals that are similar in structure, which is EPA's current practice. Furthermore, EPA should consider using the recommended approach for future cumulative risk assessments on other kinds of chemicals.

Phthalates are used in a wide variety of consumer products, such as cosmetics, medical devices, children's toys, and building materials. In light of concerns, the European Union and the United States have passed legislation that restricts the concentrations of several phthalates in children's toys, and the European Union has also banned several phthalates from cosmetics. EPA asked the Research Council to recommend whether it should conduct a cumulative risk assessment for phthalates, and if so, how it should be framed. Accordingly, the National Research Council report is not a comprehensive profile on the health effects of phthalates.

Recent animal studies have increased understanding of the potential risks from phthalates, although few human studies on the health effects of phthalates are available, said the committee that wrote the report. To decide whether a cumulative risk assessment is warranted, two factors needed to be determined: whether humans are exposed to multiple phthalates at any given time, and whether sufficient evidence exists linking exposures to similar adverse health effects. The committee established that recent studies have shown widespread human exposure to multiple phthalates, including in utero exposure.

Then, the committee reviewed animal research and found that exposure to various phthalates in lab animals produced similar health outcomes, including a range of effects on the development of the male reproductive system. The most notable effects in male rats are infertility, undescended testes, malformation of the penis, and other reproductive tract malformations. However, the severity of effects differs among phthalates; some exhibit less severe or no effects. Furthermore, the age of the animals at the time of exposure is critical to the severity of the effects. For example, the fetus is most sensitive. Given that multiple human exposures to phthalates occur and that research shows exposure to different phthalates leads to similar outcomes in lab animals, a cumulative risk assessment is called for, the committee said.

The animal studies reviewed by the committee also indicated that some phthalates reduce testosterone concentrations. Depending on when this drop occurs, it can cause a variety of effects in animals that are critical for male reproductive development. Other chemicals known as antiandrogens, which prevent or inhibit male hormones from working, can produce similar effects in lab animals. The committee recommended that phthalates and other chemicals that affect male reproductive development in animals, including antiandrogens, be considered in the cumulative risk assessment. A focus solely on phthalates to the exclusion of other chemicals would be artificial and could seriously underestimate risk, the committee emphasized.

Currently when conducting cumulative risk assessments, EPA often considers only chemicals that are structurally related, on the assumption that they have the same chain of reactions that lead to a final health outcome. That practice ignores how exposures to different chemicals may result in the same health effects. The conceptual approach taken for phthalates -- to consider chemicals that cause similar health effects -- should also be applied when completing any cumulative risk assessment, the committee said. For instance, EPA could evaluate the risk of combined exposures to lead, methylmercury, and polychlorinated biphenyls because all contribute to cognitive deficits consistent with IQ reduction in children.

In addition, further research should be conducted to allow greater refinement of the cumulative risk assessment associated with phthalates and reduce uncertainty associated with such an assessment, the report says. Moving beyond the constraints of grouping chemicals based on structural similarity may appear challenging, but it is feasible to evaluate the multiplicity of human exposures. It also directly reflects EPA's mission to protect human health, the committee noted. Such a shift in approach would entail substantial efforts by EPA, such as defining and setting priorities among the most prominent adverse health effects. However, a focus on similar outcomes facilitates the process by identifying the groups of chemicals that should be included.


'/>"/>

Contact: Jennifer Walsh
news@nas.edu
202-334-2138
National Academy of Sciences
Source:Eurekalert

Related medicine news :

1. Stakeholders and public should use 20 specific health indicators
2. Patient consent forms should educate not intimidate
3. Rochester Shoulder Surgeon Blends Innovative Techniques with Personalized Patient Care
4. Regence Supports Meaningful Health Reforms; Unveils Poll Saying Nations Economic Woes Shouldnt Delay Reforms
5. AAPS Applauds the Resignation of TMB President Roberta Kalafut, Mari Robinson Should Resign Next
6. People who want access to the NHS should behave more responsibly, says expert
7. Parents of new babies should be considered for a whooping cough booster, say experts
8. FTC Acts to Prevent Tobacco Industry Deception About Tar, Nicotine Levels; Congress Should Give FDA Authority Over Tobacco Products
9. Why women should eat less, move more and consider wearing transdermal HRT patches during menopause
10. States Should Fund Quit-Smoking Treatments: Experts
11. CDC Reports Drop in Adult Smoking, But Death Toll and Health Costs Are Still Growing; Congress, States Should Implement Proven Solutions
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:6/26/2016)... ... ... Quality metrics are proliferating in cancer care, and are derived from many ... the beholder, according to experts who offered insights and commentary in the current issue ... the full issue, click here . , For the American Society of Clinical ...
(Date:6/26/2016)... Aliso Viejo, California (PRWEB) , ... June 26, 2016 , ... ... for Final Cut Pro X. , "Film editors can give their videos a whole ... artistically," said Christina Austin - CEO of Pixel Film Studios. , ProSlice Levels ...
(Date:6/26/2016)... ... June 26, 2016 , ... Brent Kasmer, a legally blind and certified personal trainer is helping ... fitness app. The fitness app plans to fix the two major problems leading the fitness ... size fits all type program , They don’t eliminate all the reasons people ...
(Date:6/25/2016)... ... 25, 2016 , ... Experts from the American Institutes for ... Meeting June 26-28, 2016, at the Hynes Convention Center in Boston. , AIR ... care planning, healthcare costs and patient and family engagement. , AIR researchers will ...
(Date:6/25/2016)... ... 25, 2016 , ... The temporary closing of Bruton Memorial Library on June 21 due to ... a new, often overlooked aspect of head lice: the parasite’s ability to live away from ... common occurrence, but a necessary one in the event that lice have simply gotten out ...
Breaking Medicine News(10 mins):
(Date:6/23/2016)... June 23, 2016 Bracket , a leading ... next generation clinical outcomes platform, Bracket eCOA (SM) 6.0, ... June 26 – 30, 2016 in Philadelphia ... Clinical Outcome Assessment product of its kind to fully integrate ... Bracket eCOA 6.0 is a flexible platform for electronic ...
(Date:6/23/2016)... and INDIANAPOLIS , June ... receiving a Lilly Diabetes Tomorrow,s Leaders Scholarship is any ... scholarship winners, announced today online at www.diabetesscholars.org ... type 1 diabetes stand in the way of academic ... supported the Foundation,s scholarship program since 2012, and continues ...
(Date:6/23/2016)... June 23, 2016 Revolutionary technology ... Oticon , industry leaders in advanced audiology and ... Oticon Opn ™, the world,s first internet connected ... for IoT devices.      (Photo: http://photos.prnewswire.com/prnh/20160622/382240 ... a number of ,world firsts,: , TwinLink™ ...
Breaking Medicine Technology: