Lake Erie Rehabilitated: Controlling Cultural Eutrophication 1960s-1990s

Chapter IX: Concerns about NTA Use

given developments concerning detergents during 1970— that government, industry, and the public understood that phosphates in detergents would have to be replaced; that the most promising replacement , NTA, was already being incorporated in detergents; and that if NTA were completely to replace phosphate, then some two billion pounds of it would be discharged into the aquatic environment annually1 —concern had been expressed, especially in the United States, by government officials , industrial representatives, and members of the public, about possible adverse environmental effects of NTA. However, the less frequently expressed concern about the implications for human health of the use of NTA became the dominant concern in the United States from December 1970. The subsequent examination of NTA in regard to the implications of its use in detergents for both human health and the environment would be so thorough that NTA would come to be regarded as one of the most tested materials in history.2 In the United States, Allen Hirsch of the Federal Water Pollution Control Administration (FWPCA) wrote, in March 1970, to the office of the surgeon general, raising questions regarding possible public health problems which might emerge as a consequence of widespread use of substi143 Concerns about NTA Use C H A P T E R I X tutes for phosphates in detergents. Regarding NTA, he noted that its strong chelating properties could create problems involving toxic heavy metals.3 A chelate is a complex of a chemical, say NTA, and a metal, say lead, written as lead/NTA. Such a chelate could be formed in sewage and discharged into receiving waters. There the complex would break down when the NTA degraded, releasing the lead into water that might be used as a source of domestic water supply.4 As a consequence of Hirsch’s letter, a meeting on the use of NTA as a substitute for phosphate in detergents was held on April 24, attended by representatives of the Environmental Health Service (EHS), Food and Drug Administration (FDA), Federal Water Quality Administration (FWQA), and the National Institute of Environmental Health Sciences (NIEHS). The NIEHS, created in 1969, was particularly concerned with the adverse effects on human health of long-term exposure to low concentrations of biological, chemical, and physical substances. Its work was intended to provide a scientific basis for protective and preventive measures taken by the regulatory agencies having environmental responsibilities .5 Regarding heavy-metal chelation, the NIEHS representative, Hans L. Falk, stated that a “good fix” on this problem could be obtained within a short time from mutagenicity and teratogenicity (the power to cause, respectively , genetic change and fetal malformation) studies with animals, but that carcinogenicity studies would take several years.6 Two weeks later, on May 6, several of these same representatives and others met with representatives of the detergent industry and its NTA suppliers specifically to discuss the public health implications of substituting NTA for phosphate in detergents.7 Consideration of the environmental effects of NTA, including effects on algae, was deferred to a future meeting. Arthur Wolff of the EHS commented that, while results of acute toxicity studies of NTA appeared satisfactory, long-term chronic studies were lacking . Neil Chernoff, the NIEHS representative at this meeting, related that the institute was conducting two studies: teratology in animals induced by exposure to NTA before pregnancy and by exposure during the period of organogenesis. At a June meeting, Chernoff and his colleague Diane Courtney were asked to submit a report on these studies by the end of November .8 Because of the limited time, they would confine their research to the effects of subcutaneous and oral doses of NTA, cadmium/NTA, and methylmercury/NTA in rats and mice. 144 Concerns about NTA Use Meanwhile, on May 6, Samuel S. Epstein, senior research associate in pathology at the Children’s Cancer Research Foundation in Boston, and research associate in pathology at Harvard Medical School, testified before the Senate’s Subcommittee on Air and Water Pollution regarding potential biological hazards posed by nitrates and NTA in water supplies.9 Noting that complete substitution of polyphosphates by NTA in detergents could result in an annual usage in the U.S. of approximately two billion pounds of NTA within two years,10 he reviewed the data on the biodegradability and toxicology of NTA and argued that “The proposed extensive use of NTA must be disallowed until detailed chemical...