After our episodes on the impact of lead on the developing brain and how microbes teeming inside us shape our health in unbelievable ways, EDF Health is proud to present the latest episode of our podcast, You Make Me Sick. On this episode, we interviewed Dr. James Meador of the National Oceanic and Atmospheric Agency about his research article where he found a soup of chemicals, including cocaine, in the waters of the Puget Sound. He explains how drugs and other chemicals of emerging concern can pass through wastewater treatment plants and end up in the surrounding waters and even the tissues of fish!
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Also posted in Health Science Tagged Podcast
Tom Neltner, J.D., is Chemicals Policy Director
Health professionals periodically ask me how they should advise parents who ask about what constitutes a dangerous level of lead in drinking water. They want a number similar to the one developed by the Environmental Protection Agency (EPA) for lead in dust and soil (which is the primary source of elevated blood lead levels in young children). I usually remind them that EPA’s 15 parts per billion (ppb) Lead Action Level is based on the effectiveness of treating water to reduce corrosion and the leaching of lead from plumbing; it has no relation to health. Then I tell them that EPA is working on one and to hold tight. Admittedly, that is not very satisfying to someone who must answer a parent’s questions about the results of water tests today.
On January 12, EPA released a draft report for public comment and external peer review that provides scientific models that the agency may use to develop potential health-based benchmarks for lead in drinking water. In a blog last month, I explained the various approaches and options for benchmarks that ranged from 3 to 56 ppb. In another blog, I described how EPA’s analysis provides insight into the amounts of lead in food, water, air, dust and soil to which infants and toddlers may be exposed. In this blog, I provide our assessment of numbers that health professionals could use to answer a parent’s questions. Because the numbers are only a start, I also suggest how health professionals can use the health-based benchmarks to help parents take action when water tests exceed those levels.
EDF’s read on an appropriate health-based benchmark for individual action on lead in drinking water
When it comes to children’s brain development, EDF is cautious. So we drew from the agency’s estimates calculated by its model to result in a 1% increase in the probability of a child having a blood lead level (BLL) of 3.5 micrograms of lead per deciliter of blood (µg/dL).
|EDF's assessment of a health-based benchmark for individual action on lead in drinking water|
|Age of child in home and type of exposure||Houses built before 1950¹||Houses built 1950 to 1978²||Tests show no lead in dust or soil³|
|Formula-fed infant||3.8 ppb||8.2 ppb||11.3 ppb|
|Other children 7 years or younger||5.9 ppb||12.9 ppb||27.3 ppb|
Tom Neltner, J.D., is Chemicals Policy Director and Maricel Maffini, Ph.D., Consultant
Virtually all types of food contain measurable amounts of perchlorate. Young children are the most highly exposed, and they consume levels that may be unsafe. Reducing exposure to perchlorate is of public health importance because it presents a risk to children’s brain development
One potentially significant source of the toxic chemical in food is hypochlorite bleach that, when not well managed, degrades to perchlorate. Bleach is used to sanitize food manufacturing equipment or to wash or peel fruits and vegetables. Thanks to a recent decision by Environmental Protection Agency’s (EPA) Office of Pesticide Programs, we will better understand the risk posed by perchlorate-contaminated bleach and whether standards are needed to improve the management of bleach.
Reduce perchlorate exposure by improving bleach management
In 2011, an excellent report by the American Water Works Association (AWWA) and the Water Research Foundation documented that hypochlorite bleach degrades into perchlorate. The report also included guidelines on better management of hypochlorite to preserve its effectiveness for drinking water utilities using it to disinfect water.
Most of AWWA’s recommendations are equally relevant to food manufacturers and anyone using bleach to disinfect food contact surfaces. The key recommendations are:
- Dilute hypochlorite solutions on delivery. Cutting the concentration in half decreases the degradation rate by a factor of 7.
- Store hypochlorite solutions at lower temperatures. Reducing temperature by 5oC decreases degradation rate by a factor of 2.
- Keep pH between 11 and 13 even after dilution.
- Avoid extended storage times, and use fresh hypochlorite solutions when possible.
The objective is not to reduce the use of bleach. Rather it is to preserve its effectiveness by preventing degradation to perchlorate through careful management.
Bleach: a food additive and a pesticide
Also posted in Drinking Water, FDA, Food, perchlorate, Regulation Tagged Bleach, chlorate, degradation, food additive, hypochlorite, perchlorate, pesticide
Tom Neltner, J.D., is Chemicals Policy Director
On January 19, the Environmental Protection Agency (EPA) released a major new draft report proposing three different approaches to setting health-based benchmarks for lead in drinking water. We applauded EPA’s action and explored the implications for drinking water in a previous blog. One of the agency’s approaches provides useful, and surprising, insights into where the lead that undermines the health of our children comes from. Knowing the sources enables regulators and stakeholders to set science-based priorities to reduce exposures and the estimated $50 billion that lead costs society each year.
The EPA draft report is available for public comments until March 6, 2017, and it is undergoing external peer-review by experts in the field in support of the agency’s planned revisions to its Lead and Copper Rule (LCR) for drinking water. Following this public peer-review process, EPA expects to evaluate and determine what specific role or roles a health-based value may play in the revised LCR. With the understanding that some of the content may change, here are my takeaways from the draft:
- For the 20% of most exposed infants and toddlers, dust/soil is the largest source of lead. Since we know that 21% of U.S. homes (24 out of 114 million) have lead-based paint hazards, this should not be surprising.
- For most infants, lead in water and soil/dust have similar contributions to blood lead levels, with food as a smaller source. If the infant is formula-fed, water dominates.
- For 2/3 of toddlers, food appears to provide the majority of their exposure to lead. This result was a surprise for me. EPA used data from the Food and Drug Administration’s (FDA) Total Diet Study collected from 2007 to 2013 coupled with food consumption data from the National Health and Nutrition Examination Survey collected from 2005 to 2011. In August 2016, FDA reported on levels of lead (and cadmium in food) commonly eaten by infants and toddlers based on a data set that is different from its Total Diet Study. FDA concluded that these levels, “on average, are relatively low and are not likely to cause a human health concern.”
- For all children, air pollution appears to be a minor source of lead exposure. We think it is most likely because exposure is localized around small airports and industrial sources.
For a visual look at the data, we extracted two charts from the draft EPA report (page 81) that show the relative contribution of the four sources of lead for infants (0-6 month-olds) and toddlers (1 to <2 year-olds) considered by the agency. The charts represent national exposure distributions and not specific geographical areas or age of housing.
Also posted in Drinking Water, EPA, FDA, Food, Health Policy, lead Tagged Drinking Water, dust, EPA, Food, lead, paint, soil
A non-estrogenic alternative to Bisphenol A at last?
Sarah Vogel, Ph.D., is Vice-President for Health.
Last week a new study was published showing promising results for a non-estrogenic alternative to polymers based on bisphenol A (BPA) used to line the inside of food cans. The paper, in Environmental Science & Technology (ES&T), evaluated the estrogenicity of an alternative to BPA— tetramethyl bisphenol F (TMBPF) — and its final polymer product developed by Valspar, a major paint and resin company. The authors found that, unlike BPA and some of its analogs that have been used as substitutes, TMBPF exhibited no signs of estrogenicity.
This was an unusual paper on a number of fronts—how the material was selected, how it was evaluated and by whom. In this post I’m going to explore who was involved, what testing was done and what this might mean for the BPA alternatives market.
Richard Denison, Ph.D., is a Lead Senior Scientist. Lindsay McCormick is a Project Manager.
Today, EPA issued its long-awaited rule to gather risk-relevant information on nanoscale materials. The new rule will finally allow EPA to obtain basic data on use, exposure, and hazards from those that manufacture or process these materials, which has long been recognized by experts as essential to understand and manage their potential risks.
Nanomaterials – a diverse category of materials defined mainly by their small size – often exhibit unique properties that can allow for novel applications but also have the potential to negatively impact our health and the environment. Some nanomaterials: more easily penetrate biological barriers than do their bulk counterparts; exhibit toxic effects on the nervous, cardiovascular, pulmonary, and reproductive systems; or have antibacterial properties that may negatively impact ecosystems or lead to resistance.