Table 1

Summary of animal toxicological assessments of reproductive effects of chlorination disinfection byproducts

Byproduct	Usual concentration in drinking water	Doses given in drinking water or gavage (mg/kg/day)	Teratogenic effects	Reference (year)
Chloral hydrate	<20 μg/l	16 and 160 mg/kg	No adverse effects on body weight or malformations found	Kallman et al 12 (1984)
		55 and 188 mg/kg	Decreased sperm motility in male rats at highest dose only	Klinefelter13 (1995)

Trihalomethanes:
Chloroform		<100 μg/l		100–400 mg/kg orally	Reduced foetal body weight at highest dose, evidence for fetotoxic response, no teratogenic effects	Ruddick et al 14(1983)
				0–126 mg/kg orally	No evidence of teratogenicity, reduced foetal weight only at highest dose	Thompsonet al 15 (1974)
				30–300 ppm inhalation	Growth retardation and minor skeletal aberrations at all concentrations and minor embryo and fetotoxicity at high concentrations	Schwetz et al 16 (1974)
				0–100 ppm inhalation	Pregnancy loss, reduced foetal body weight and crown-rump length at high dose	Murray et al 17 (1979)
Bromoform		<6 μg/l		0–200 mg/kg	No effect on fertility or reproduction indices, including sperm density, motility, and morphology	Gulati et al 18(1989)
Bromoform		<6 μg/l		100–400 mg/kg orally	Evidence for fetotoxic response, no effect on foetal weight, no teratogenic effects	Ruddicket al 14 (1983)
Bromodichloromethane (BDCM)		<50 μg/l		50–200 mg/kg orally	No reduction in foetal body weight, no fetotoxic response, no teratogenic effects	Ruddick et al 14 (1983)
				25–75 mg/kg	Foetal resorption at 50 and 75 mg/kg doses. No effect on duration of gestation, pup survical, weight, and morphology	Narotsky et al 19 (1997)
				22 and 39 mg/kg	Decreased sperm motility in male rats at highest dose only	Klinefelter13(1995)
				0–1500 ppm orally	No findings related to treatment in male and female reproductive variables	NTP20 (1999)
				5.8–40.3 mg/kg/day orally	No reprotoxicological effects in males and females	Delaney et al 21 (1997)
Chlorodibromomethane (CDBM)	<45 μg/l	50–200 mg/kg orally	No foetal weight reduction, evidence of fetotoxic response, no teratogenic effect	Ruddick et al 14 (1983)
		0–685 mg/kg	Decreased litter size, and pup viability at high dose, slight depression of foetal weight	Borzellecaet al 22 (1982)

Chlorophenols	<1 μg/l		3–300 mg/kg	CP: increased conception rate and stillbirth; reduction in size of litters at highest dose only	Exon et al 23 (1985)
2-Chlorophenol (CP)			3–300 mg/kg		DCP: No adverse effect on reproductive performance		Exon et al 24(1994)
2,4-Dichlorophenol (DCP)			3–300 mg/kg		DCP: No adverse effect on reproductive performance		Exon et al 24(1994)

Halogenated acetic acids:
Dicholoroacetic acid (DCAA)	<100 μg/l	14–2400 mg/kg	DCAA: increased embryonic resorption = 900 mg/kg, reduction in body weight and cardiac malformations =140 mg/kg	Smith et al 25 (1992)
		0–125 mg/kg/day	DCAA: inhibited spermiation at highest dose, reduced epidymal sperm counts and sperm motility, sperm morphology impacted also at lower doses	Toth et al 26 (1992)
		0–3000 mg/kg/day	DCAA: delayed spermiation, decreased sperm motility and morphologic abnormalities	Linder et al 27(1997)
Trichloroacetic acid (TCAA)		330–1800 mg/kg	TCAA: increased embryonic resorption, reduction in body weight and increase in cardiovascular malformations at all doses. Skeletal malformations found at highest dose only	Smithet al 28 (1989)
Monobromoacetic acid (MBAA)		0–100 mg/kg/day	MBAA: no effects	Linder et al 29 (1994)
Dibromoacetic acid (DBAA)			0–270 mg/kg/day	DBAA: reduced epididymal sperm counts and sperm motility, morphological changes	Linder et al 30 (1994)
			0–1250 mg/kg/day	DBAA: Sperm motility and morphology effected	Linder et al 29(1994)
			0–250 mg/kg	DBAA: reduction in sperm motility and sperm count at highest dose only, and moderate changes at lower doses	Linder et al 31 (1995)
			0–250 mg/kg/day	DBAA: spermatid changes	Linderet al 32 (1997)

Halogenated acetonitriles:
Dichloroacetonitrile (DCAN)	<10 μg/l mostly <1 μg/l	1–55 mg/kg	DCAN: increased foetal resorption and reduction in foetal body weight with increasing dose. Cardiovascular, skeletal, and urogenital malformations ⩾45 mg/kg.	Smithet al 33 (1987)
Trichloroacetonitrile (TCAN)		1–555 mg/kg	TCAN: increased foetal resorption and reduction in foetal body weight with increasing dose. Cardiovascular and urogenital malformations at ⩾15 mg/kg. No skeletal defects found.	Smith et al 34 (1989) Smith et al 35 (1988)

Hydroxyfuranone (MX)	<0.1 μg/l		No data

Chlorinated acetones	<1 μg/l		No data