Research Product

Acute static or flow-through bioassays generally have been used to set marine water quality standards, but few new bioassay techniques are available to determine long-term effects of one or more toxicants on survival, growth and reproduction of individual species of mollusks, arthropods or fish and on communities of estuarine organisms. Not only has the duration of bioassays increased from 96 hours or less to periods of from one month to two years, but the complexity has increased as well. Effects of toxicants on the entire life-cycle of an oviparous estuarine fish, Cyprinodon variegatus, can now be studied; one bioassay with endrin has been completed. This fish typically develops from an embryo to maturity in 10 weeks, with about 70% survival overall. Females produce an average of eight eggs per day and fertilization success exceeds 90%. Effects of a polychlorinated biphenyl, AroclorŪ 1254, and a pesticide, toxaphene, on developing communities of estuarine animals have been investigated. These studies provide data for prediction of pollution-induced shifts in composition of estuarine animal communities.