Dental school and professional practice are well‐documented sources of stress. Although students and dentists risk developing stress‐related disorders, no empirically evaluated method for helping dental students cope with stress has been reported. A group of 17 dental students participated in a six‐session program that included instruction in self‐relaxation and time management; exercise and leisure planning; and cognitive modification techniques. From pre‐ to post‐training, subjects showed improvement on a variety of self‐report and physiological measures relative to a waiting‐list control group. A three‐month follow‐up assessment revealed continued reductions in stress‐related behavior. The importance of stress‐management training for dental students is discussed as well as suggestions for future research.

We have developed methods for obtaining embryos and conducting early life-stage toxicity tests (continuous exposure from the embryonic stage to approximately three weeks or more into the exogenous feeding stage) with three estuarine species of atherinid fishes. Early life-stage tests were conducted for 28 days with Menidia beryllina, M. menidia, and M. peninsulae and the insecticide chlorpyrifos. Responses of the three species were similar: upper chronic values (“effect” concentrations) ranged from 0.48 to 1.8 µg chlorpyrifos/L and lower chronic values (“no effect” concentrations) ranged from 0.28 to 0.75 µg/L. Chlorpyrifos exposure did not affect survival of embryos to hatching which averaged 91 to 93% for each species. In treatments in which no adverse effects were observed, combined survival of M. menidia embryos and hatched fish averaged 51% and fish weights averaged 23 mg; for M. peninsulae, 69% and 13.6 mg; and for M. beryllina, 81% and 8.7 mg. Chlorpyrifos bioconcentration factors (concentration in whole fish ÷ average measured concentration in water) averaged 220 for M. beryllina, 460 for M. peninsulae, and probably < 420 for M. menidia. From these three species, toxicologists may select an Atlantic or Gulf Coast species that occurs in either high or low salinity.

Entire life-cycle toxicity tests are practical with sheepshead minnows, Cyprinodon variegatus. This is the only estuarine fish that has been utilized successfully in life-cycle toxicity tests, using methods formulated only since 1973. Salinity, temperature, and spawning requirements were determined, and initial life-cycle toxicity tests with endrin were conducted at the U.S. Environmental Protection Agency Gulf Breeze (Florida) Laboratory. Subsequent tests with heptachlor, carbofuran, methoxychlor, and malathion were conducted at Gulf Breeze or at EG&G, Bionomics. All studies confirmed the feasibility of using this estuarine fish for determining maximum acceptable toxicant concentrations and application factors. Results of our tests also corroborate data on application factors obtained in studies completed elsewhere with freshwater fishes and the same pesticides.

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