Front Matter

172 Autism and Exposure to Environmental Chemicals

Table 7.1 Widespread pollutants with endocrine‐disrupting effects.

Compound(s) Hormone Mechanism

Persistent Organohalogens

Benzene hexachloride Thyroid Unknown

1,2‐Dibromoethane Reproductive Unknown

Chloroform Reproductive Unknown

Dioxins and furans Estrogen Work as anti‐estrogen

through binding with Ah

receptor, which then inhibits

estrogen receptor binding to

estrogen response elements,

thereby inhibiting estrogen

action

Octachlorostyrene Thyroid Unknown

PBBs Estrogen/Thyroid Unknown

PCBs Estrogen/androgen/

Thyroid

Adverse outcomes in

reproductive systems

Inhibits estrogen binding to

the receptor; works as

anti‐estrogen

Anti‐androgenic via Ah

receptor interaction

PCB, hydroxylated Thyroid Binds to thyroid hormone

binding protein, but not to

the thyroid hormone receptor

PBDEs Thyroid Interfere with thyroxine (T4)

binding with transthryetin

Pentachlorophenol Thyroid Reduces thyroid hormone

possibly through a direct

effect on the thyroid gland

Food Antioxidant

Butylated

hydroxyanisole

Estrogen Inhibits binding to the

estrogen receptor.

Pesticide

Acetochlor Thyroid (decrease of

thyroid hormone

levels, increase in TSH)

Unknown

Alachlor Thyroid (decrease of

thyroid hormone

levels, increase in TSH)

Unknown

Aldrin Estrogen Binds to estrogen receptors;

competes with estradiol