The ultraviolet (UV) filter 3-benzylidene camphor (3BC) is used in personal care products and in a number of materials for UV protection. 3BC has been shown in vitro and in vivo in fish to be estrogenic, but possible effects on fertility and reproduction are unknown. In this study we evaluate whether 3BC affects reproduction of fish Pimephales promelas. After a preexposure period of 21 days, reproductively mature fathead minnows were exposed to increasing concentrations of 3BC for 21 days in a static-renewal procedure. Actual 3BC concentrations decreased to 23% of initial levels and median concentrations were 0.5, 3, 33, 74, and 285 microg/l. 3BC affected reproduction in a dose-dependent manner with weak effects on fecundity at 3 microg/l, a significant decrease at 74 microg/l, and a cessation of reproduction at 285 microg/l. 3BC was accumulated in fish with an average bioconcentration factor of 313 +/- 151. Dose-dependent demasculinization in secondary sex characteristics of male fish and dose-dependent induction of plasma vitellogenin occurred, which was significant at 74 microg/l and higher. 3BC had a profound and dose-dependent effect on the histology of gonads of male and female fish at 3 microg/l and higher. At 74 and 285 microg/l, oocyte and spermatocyte development was inhibited in male and female gonads. Testes of exposed males had much fewer spermatogenic cysts, and ovaries of exposed females had much fewer mature but more atretic, follicles. This study shows significant effects of the UV filter 3BC on fertility, gonadal development, and reproduction of fish after short-term exposure that may have negative consequences on the population level.

Abstract-Nonconsumptive mortality of mesozooplankton in Lake Constance was directly estimated by collecting dead zooplankton with sediment traps. Patterns of zooplankton sedimentation observed in the sediment trap reflected the population dynamics in the pelagic zone. The migration of Cyclops vicinus toward the sediment (where they spend their diapause) at the end of May resulted in a pronounced occurrence in the traps (migration rate Ͼ10 6 individuals (ind.) m Ϫ2 d Ϫ1 ). Other copepods and Daphnia hyalina had only sedimentation losses of 0.5 and 0.2% of the standing stock per day, respectively, demonstrating the minor role of nonconsumptive mortality for these species. In contrast, nonconsumptive mortality had a high significance on the population dynamics of nonmigrating epilimnetic Daphnia galeata. High sedimentation rates (up to 3 ϫ 10 3 ind. m Ϫ2 d Ϫ1 ; in total, 38% of the total population decline from 16 ϫ 10 4 to 1 ϫ 10 4 ind. m Ϫ2 within 21 d) in June 1993 were attributed to an unidentified infection. From April to November, losses of D. galeata as a result of nonconsumptive mortality (average of 2.3% of standing stock per day) accounted on average for 23% of the estimated production (10% of the standing stock per day).

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Abstract. Source control i.e. the reduction of contamination from upstream or diffuse sources, is a critical element in any management plan for contaminated waterways. If source control measures are not successfully implemented, then a situation exists in which contamination will continue through time, and the cleanup of waterway segments becomes increasingly problematic. To provide greater understanding of the issues surrounding source control, it is essential to have some knowledge of contaminant sources and transport pathways of contaminated particulates. In port areas a plethora of factors interact to control contaminant transport pathways. These include: rain and river flow; tidal circulation, surface waves and wind drift, and temporally changing water column stratification. Particle tracking offers a practical means to map the transport pathways of contaminated sediments under these collective influences. This paper introduces a new and novel "dual signature" tracer product, and describes the particle tracking technique on a practical level through a study example in the Lower Duwamish Waterway, Washington, USA.