Lab Matters Fall 2017 | Page 16

from the bench

by Kim Krisberg, writer

It’ s also an exercise in optimizing public health lab capacity to measure regional environmental contaminants.

“ I think this is one of the most relevant grant-funded projects we do,” said Eric Petty, chemistry program manager within the Colorado Department of Public Health and Environment’ s Laboratory Services Division and his state’ s lead for 4CSBC.“ It produces so much meaningful data and it’ s pretty unlimited regarding the number of studies we can design. There’ s so much out there that hasn’ t been looked at.”

2,4-Dichlorophenoxyacetic acid— otherwise known as 2,4-D— is the active ingredient in a variety of weed killers and one of the most common, widely used herbicides in the world. Studies in lab animals have found that high doses of 2,4-D are associated with negative heath effects. Research on human exposure is more of a mixed bag.

According to the Agency for Toxic Substances and Disease Registry, it doesn’ t appear that contact with small amounts of 2,4-D is harmful to people. Some studies on workers with relatively high exposure rates, such as professional herbicide applicators, have identified a possible link to cancers of the lymphatic system. Other studies found no strong evidence between 2,4-D and cancers. The US Environmental Protection Agency says there’ s not enough evidence to either refute or support 2,4-D as a human carcinogen, while the International Agency for Research on

Cancer has deemed 2,4-D as“ possibly carcinogenic” based on“ inadequate evidence in humans and limited evidence in experimental animals.” In other words, we need more research.

One place where research is happening is inside the public health labs of Arizona, Colorado, New Mexico and Utah, where a collaborative known as the Four Corners States Biomonitoring Consortium( 4CSBC) hopes to gather new insights into environmental exposures that could impact people’ s health. With funding from the US Centers for Disease Control and Prevention’ s( CDC’ s) National Biomonitoring Program, 4CSBC began its work in 2014, building on the previous efforts of the Rocky Mountain Biomonitoring Consortium, of which all four states had been a member. The collaborative’ s day-to-day mission is to generate the data on environmental contaminants that can inform protective public health actions.

The consortium is focused on three main studies: heavy metal exposure from private well drinking water; pesticide, herbicide and phthalates exposure; and the San Luis Valley( Colorado) Children’ s Study, which assesses hazardous chemical exposure among children ages 3 to 13. In each state, public health labs partner with environmental health workers and epidemiologists to recruit residents who want to take part, collect water and urine samples for testing, and eventually reconnect with residents to discuss results and any health-protective recommendations. The 4CSBC labs spread out the testing responsibilities according to capacity, so as to not burden any one state. Testing results are interpreted, in part, by using baseline data from CDC’ s National Health and Nutrition Examination Survey.

“ We have similar geological settings, we all have a legacy of mining in heavy metals, we’ re agricultural states, our populations can be sparse, we have common problems regarding arsenic and pesticides,” said Sanwat Chaudhuri, PhD, 4CSBC’ s principal investigator and scientific advisor for chemical and environmental services at the Utah Public Health Laboratory.“ It just makes more sense that we work together to try to solve our problems.”