7091

• UCREFRP Catalog Number: 7091
• Author: Eisler, R.
• Title: Tin Hazards to Fish, Wildlife, and Invertebrates
• USFW Year: 1989.
• USFW - Doc Type: A Synoptic Review.
• Copyright Material: NO

LETHAL AND SUBLETHAL EFFECTS
GENERAL
Inorganic tin compounds are of low toxicologic risk due largely to their
low solubility, poor absorption, low accumulations in tissues, and rapid
excretion. By contrast, some organotin compounds--especially trialkyl-
tins--produce a variety of harmful effects resulting in impaired behavior and
lowered growth, survival, and reproduction. Among aquatic organisms,
tributyltin compounds were especially potent. Adverse effects were noted in
molluscs at water concentrations of 0.001 to 0.06 ug/1 and in algae, fish, and
other species of invertebrates at 0.1 to 1.0 ug/1. Bioconcentration of
organotins was high, but degradation was sufficiently rapid to preclude food
chain biomagnification. Birds seem to be relatively resistant to organotins,
although data are extremely scarce. Preliminary data suggest that diets
containing 50 mg of tin as trimethyltin chloride/kg are fatal to all mallard
ducklings in 75 days; however, no deaths occurred in 75 days at 50 mg/kg of
eleven other mono-, di-, tri-, and tetraalkyltin compounds. Trimethyltin was
lethal to other species of birds tested at doses of 1 to 3 mg/kg body weight.
Trimethyltins and triethyltins were the most toxic organotin compounds tested
on small laboratory mammals. Neurotoxicological effects of trimethyltins were
usually not reversible, while those caused by triethyltins were reversible
after exposure. Adverse effects of trimethyltins were produced at
concentrations as low as 0.15 mg/l in drinking water (learning deficits),
0.625 mg/kg BW (diet aversion), and 1.25 mg/kg BW (death).
AQUATIC ORGANISMS
Results of acute toxicity tests with several organotin compounds and
Daphnia magna indicated several distinct trends: toxicity increased with
length of alkyl group from methyl to butyl; the anion substituents are
relatively unimportant; and bioavailability is correlated with increasing
solubility in lipids, which is a direct function of Kow, the n-octanol/water
partition coefficient (Vighi and Calamari 1985). Structure-activity relations
seem to have high predictive capacity in hazard assessment, and those for
organotins seem particularly promising (Vighi and Calamari 1985). For example,
studies on the biocidal properties of structurally distinct diorganotins
(R2SnX2) and triorganotins (R3SnX) to zoeae of a marine crab show, within a
35