Mother’s of Children with Neurological Deficits from Two Continents Have High Blood Levels of Insecticides from Technical Chlordane-Treated Homes

Delays in mental and psychomotor development at 18 months in Japanese children born to mothers with higher levels of heptachlor epoxide in their blood (The Hokkaido Study on Environment and Children’s Health) is similar to the results of another recent hospital-based prospective study conducted in the United States (The HOME – Health Outcomes and Measures of the Environment – Study) (1, 2). In the HOME Study, mothers with higher levels of trans-nonachlor and oxychlordane (3) in their blood during gestation had an increased in Autistic behaviors in their 4- and 5- year old children.

The Hokkaido Study measured 29 organochlorine pesticides (OCPs); whereas, the HOME Study measured 59 endocrine-disrupting chemicals (6 OCPs) in mother’s blood during gestation but not heptachlor epoxide.  In both studies, the organochlorine compounds derived from technical chlordane were linked to neurological deficits in children.  Technical chlordane is a mixture of four main components trans-chlordane 24±2 %, cis-chlordane 19±3 %, trans-nonachlor 7±3 %, and heptachlor 7% (4). In humans and animals, the trans- and cis-chlordanes and heptachlor are metabolized to the stabile epoxides, oxychlordane and heptachlor epoxide, respectively.  The nine chlorines on trans-nonachlor blocks epoxide formation. With exposure, heptachlor epoxide, oxychlordane, and trans-nonachlor accumulate in lipid compartments of the body (5, 6).

The Home Study only allowed expecting mothers from homes built prior to 1978. This restriction increased the odds that the participating mothers lived in a technical chlordane-treated home.

Both Japan and the United States banned technical chlordane for agriculture in the 1970s but continued technical chlordane use for termite-treatment of homes until 1986 and 1988, respectively.  Multiple studies conducted world-wide in the late 1990s and early 2000s showed that Americans and Japanese had some of the highest levels of oxychlordane, heptachlor epoxide, and nonachlor in their blood (7, 8) and breast milk (9). The main route of exposure is via breathing the contaminated indoor air of technical chlordane-treated homes resulting in much higher body burdens in dwellers 10, 11).  In the United States, >90% of the daily exposure to heptachlor and chlordane were derived from breathing the indoor air in treated homes (12). Over 80 million Americans lived in homes treated with technical chlordane; however, their exposures varied over a hundred thousand-fold with measurements from <1 to 610,000 nanograms gram per cubic meter of air (ng/m³) (8).

American and Japanese women considering starting a family or having additional children should test homes built before 1990 for indoor levels of heptachlor, cis- and trans-chlordane. Proper installation of an exhaust fan in a crawl space; or an Energy-Recovery-Ventilation System in a basement or interfaced to the ducting of a forced-air home system can remove 90-98% of technical chlordane compounds from the air.

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REFERENCES:

1. Yamazaki, K. et al. 2017. Association between prenatal exposure to organochlorine pesticides and mental and psychomotor development of infants at ages 6 and 18 months: The Hokkaido Study on Environment and Children’s Health.  Neurotoxicology. https://doi.org/10.1016/j.neuro.2017.11.011
2. Braun, J. M. et al. 2014. Gestational exposure to endocrine disrupting chemicals and reciprocal social, repetitive and stereotypic behaviors in 4- and 5-year-old children: The HOME Study. Environmental Health Perspectives. 122:513-520. https://dx.doi.org/10.1289/ehp.1307261
3. Personal Communications with BPL. (see Methods: The chemical with the higher median concentration was chosen when two chemicals were highly correlated).
4. Sovocool, G. W. et al. 1977. Analysis of technical chlordane by gas chromatography/mass spectrometry. Anal Chem. 49:734-740. http://pubs.acs.org/doi/abs/10.1021/ac50014a018
5. Kanazawa, A. et al. 2012. Blood persistent organochlorine pesticides in pregnant women in relation to physical and environmental variables in The Hokkaido Study on Environment and Children’s Health. Sci Total Environ. 426:73-82.   https://www.ncbi.nlm.nih.gov/pubmed/22503674
6. Zong, G, et al. 2015. Circulating Persistent Organic Pollutants and Body Fat Distribution, Evidence from NHANES 1999-2004. Obesity. 23:1903–1910.   https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4551580/
7. Minh. T.B. et al. 2005. Human blood monitoring program in Japan: Contamination and bioaccumulation of persistent organochlorines in Japanese residents. Archive of Environmental Contamination and Toxicology. 51:296-313. http://dx.doi.org/10.1007/s00244-004-0
8. Agency for Toxic Substances and Disease Registry (1994) Toxicological profile for chlordane. Atlanta, GA. United States Department of Health; and Human Services. Public Health Service, Agency for Toxic Substances and Disease Registry. https://www.atsdr.cdc.gov/toxprofiles/tp31.pdf
9.  Konishi, Y. et al. 2001. Continuous surveillance of organochlorine compounds in human breast milk from 1972 to 1998 in Osaka, Japan. Arch. Environ. Contam. Toxicol. 40:571-578.  https://www.ncbi.nlm.nih.gov/pubmed/11525502
10. Taguchi, S. and Yakushiji, T. 1988. Influence of termite treatment in the home on the chlordane concentration in human milk. Arch. Envirn. Contam. Toxicol. 17:65-71. https://link.springer.com/article/10.1007/BF01055155
11. Sim, M. et al. 1998. Termite control and other determinants of high burdens of cyclodiene insecticides. Arch. Environ. Health. 53:114-121.  https://www.ncbi.nlm.nih.gov/pubmed/9577934
12. Whitmore, R. W. et al. 1994. Non-occupational exposures to pesticides for residents of two U.S. cities. Arch. Envirn. Contam. Toxicol. 26:47-59.  http://www.nchh.org/portals/0/contents/article0283.pdf