Unusual words played today include: PIBAL (a small balloon used in weather fore-casting), YOWE (a ewe), AMITROLE
(an herbicide), SANTOUR (a Persian dulcimer) and HERL (a feathered fishing lure).
, and ethylenethiourea) decrease TH synthesis by inhibition of thyroid peroxidase (Capen 1997, 1998; Hill et al.
It was more than a decade before Freeman (1988) reported detectable levels of simazine and amitrole
in the drainage waters of Styx River from an orchard near Christchurch.
Rats and mice that were exposed to amitrole developed thyroid and liver tumors (Council on Scientific Affairs, 1988).
TABLE 1 Some Endocrine-Disrupting and Estrogen-like Pesticides Endocrine-Disrupting Pesticides Herbicides 2,4,5-T 2,4-D Alachlor Amitrole Atrazine Metribuzin Nitrofen Trifluralin Insecticides [beta]-Hexachlorocyclohexane ([beta]-HCH) Carbaryl Chlordane Dicofol Dieldrin DDT and its metabolites Endosulfan Heptachlor and H-epoxide Lindane Methomyl Methoxychlor Mirex Oxychlordane Parathion Synthetic pyrethroid Toxaphene Estrogen-like Pesticides Herbicides 2,4,5-T Insecticides [beta]-HCH Kepone (chlordecone) I-Hydroxychlordene Dicofol Dieldrin p.
For five chemicals (amitrole
, DDT, dieldrin, PBB, DPH), the same tumors were observed from early and/or adult exposures, although the studies for amitrole
, DDT, and dieldrin evaluated the animals only for liver tumors.
a) The chemicals classified as mutagenic were benzidine, benzo(a)pyrene, DEN, safrole, and vinyl chloride; the chemicals classified as not mutagenic were amitrole
, diphenylhydantoin, ethylene thiourea, and polybrominated biphenyls.
Among the most widely used herbicides that interfere with the thyroid system are 2,4-dichlorophenoxyacetic acid (2,4-D), acetochlor, aminotriazole, amitrole
, bromacil, bromoxynil, pendamethalin, and the thioureas (Brucker-Davis 1998; Howdeshell 2002; Short and Colborn 1999).