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/l16 and 160 mg/kgNo adverse effects on body weight or malformations foundKallman et al 12 (1984)
55 and 188 mg/kgDecreased sperm motility in male rats at highest dose onlyKlinefelter13 (1995)
Trihalomethanes:
 Chloroform<100 μg/l100–400 mg/kg orallyReduced foetal body weight at highest dose, evidence for fetotoxic response, no teratogenic effectsRuddick et al 14(1983)
0–126 mg/kg orallyNo evidence of teratogenicity, reduced foetal weight only at highest doseThompsonet al 15 (1974)
30–300 ppm inhalationGrowth retardation and minor skeletal aberrations at all concentrations and minor embryo and fetotoxicity at high concentrationsSchwetz et al 16 (1974)
0–100 ppm inhalationPregnancy loss, reduced foetal body weight and crown-rump length at high doseMurray et al 17 (1979)
 Bromoform<6 μg/l0–200 mg/kgNo effect on fertility or reproduction indices, including sperm density, motility, and morphologyGulati et al 18(1989)
100–400 mg/kg orallyEvidence for fetotoxic response, no effect on foetal weight, no teratogenic effectsRuddicket al 14 (1983)
  Bromodichloromethane (BDCM)<50 μg/l50–200 mg/kg orallyNo reduction in foetal body weight, no fetotoxic response, no teratogenic effectsRuddick et al 14 (1983)
25–75 mg/kgFoetal resorption at 50 and 75 mg/kg doses. No effect on duration of gestation, pup survical, weight, and morphologyNarotsky et al 19 (1997)
22 and 39 mg/kgDecreased sperm motility in male rats at highest dose onlyKlinefelter13(1995)
0–1500 ppm orallyNo findings related to treatment in male and female reproductive variablesNTP20 (1999)
5.8–40.3 mg/kg/day orallyNo reprotoxicological effects in males and femalesDelaney et al 21 (1997)
  Chlorodibromomethane (CDBM)<45 μg/l50–200 mg/kg orallyNo foetal weight reduction, evidence of fetotoxic response, no teratogenic effectRuddick et al 14 (1983)
0–685 mg/kgDecreased litter size, and pup viability at high dose, slight depression of foetal weightBorzellecaet al 22 (1982)
Chlorophenols<1 μg/l3–300 mg/kgCP: increased conception rate and stillbirth; reduction in size of litters at highest dose onlyExon et al 23 (1985)
 2-Chlorophenol (CP)3–300 mg/kgDCP: No adverse effect on reproductive performanceExon et al 24(1994)
 2,4-Dichlorophenol (DCP)
Halogenated acetic acids:
 Dicholoroacetic acid (DCAA)<100 μg/l14–2400 mg/kgDCAA: increased embryonic resorption = 900 mg/kg, reduction in body weight and cardiac malformations =140 mg/kgSmith et al 25 (1992)
0–125 mg/kg/dayDCAA: inhibited spermiation at highest dose, reduced epidymal sperm counts and sperm motility, sperm morphology impacted also at lower dosesToth et al 26 (1992)
0–3000 mg/kg/dayDCAA: delayed spermiation, decreased sperm motility and morphologic abnormalitiesLinder et al 27(1997)
 Trichloroacetic acid (TCAA)330–1800 mg/kgTCAA: increased embryonic resorption, reduction in body weight and increase in cardiovascular malformations at all doses. Skeletal malformations found at highest dose onlySmithet al 28 (1989)
 Monobromoacetic acid (MBAA)0–100 mg/kg/dayMBAA: no effectsLinder et al 29 (1994)
 Dibromoacetic acid (DBAA)0–270 mg/kg/dayDBAA: reduced epididymal sperm counts and sperm motility, morphological changesLinder et al 30 (1994)
0–1250 mg/kg/dayDBAA: Sperm motility and morphology effectedLinder et al 29(1994)
0–250 mg/kgDBAA: reduction in sperm motility and sperm count at highest dose only, and moderate changes at lower dosesLinder et al 31 (1995)
0–250 mg/kg/dayDBAA: spermatid changesLinderet al 32 (1997)
Halogenated acetonitriles:
 Dichloroacetonitrile (DCAN)<10 μg/l mostly <1 μg/l1–55 mg/kgDCAN: 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/kgTCAN: 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/lNo data
Chlorinated acetones<1 μg/lNo data