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Archives of Environmental Contamination and Toxicology (v.43, #3)
Estrogenic Activity of Musk Fragrances Detected by the E-Screen Assay Using Human MCF-7 Cells by N. Bitsch; C. Dudas; W. Körner; K. Failing; S. Biselli; G. Rimkus; H. Brunn (pp. 0257-0264).
The widespread use of synthetic musk fragrances and the resultant presence of these substances and their metabolites in the aquatic environment (as well as their accumulation in human adipose tissue) raises the question of whether musk fragrances display endocrine and in particular estrogenic activity. A variety of musk fragrances were tested using the E-screen assay. A statistically significant increase in proliferation rate of human MCF-7 breast cancer cells was detected for two nitro musks (musk xylene, musk ketone), a major metabolite of musk xylene (p-amino-musk xylene), and the polycyclic musk fragrance AHTN. This indicates that these substances do, in fact, demonstrate estrogenic activity. Coincubation with the antiestrogen tamoxifen showed that the increase in proliferation rate by the musk fragrances is estrogen receptor–mediated. It must be noted, however, that the effective estrogenic strength and estrogenic potency were low compared to 17b-estradiol. The naturally occurring fragrance muscone from the group of macrocyclic musk fragrances, a group of substances that have not yet been well characterized in respect to their toxicological properties, has also been shown to be weakly estrogenically active in vitro. E-screen analysis showed that the nitro musk metabolites o-amino musk xylene and 2-amino-MK, the macrocyclic musk fragrances ethylene brassylate, ethylene dodecandioate, and cyclopentadecanolide, are not estrogenically active.
Bisphenol A Degradation by Bacteria Isolated from River Water by J.-H. Kang; F. Kondo (pp. 0265-0269).
Recently, there is increasing interest in the microbial degradation of endocrine disruptors. This study was conducted to show the isolation and property of bacteria having bisphenol A (BPA) biodegradability in river water and to identify the difference of BPA degradation under aerobic and anaerobic conditions. Three river water samples spiked with BPA (1 mg/L) were rapidly degraded under aerobic conditions. The half-life for BPA degradation ranged from 2 to 3 days, and BPA was below detection limit (less than 0.005 mg/L) on the 10th day. But a decrease of BPA under anaerobic conditions was hardly identified at 30°C for 10 days (less than 10%). Also, most bacteria (10 out of 11) isolated from three river waters had BPA biodegradability, but there were differences in removal rates of BPA (18% to 91%). Moreover, two strains that had high BPA biodegradability (about 90%) were identified as a Pseudomonas sp. and a Pseudomonas putida strain.
Nitrates/Nitrites Alter Human Lymphocyte Proliferation and Cytokine Production by I. V. Ustyugova; C. Zeman; K. Dhanwada; L. A. Beltz (pp. 0270-0276).
Nitrate from drinking water is converted in the body to nitrite by bacteria in the gut. This project examined effects of nitrate/nitrite on immune functions, i.e., human lymphocyte proliferation and cytokine production. Nitrate had no effect on lymphocyte growth, but nitrite decreased proliferation. Neither inhibited fibroblast growth. In 1/3 to 2/3 of the subjects tested, sodium nitrate or nitrite decreased production of Th1 cytokines (interleukin-2, interferon-γ, and tumor necrosis factor-β). Nitrate and nitrite either increased or had no effect on the production of the Th2 cytokine interleukin-10. A Th1 immune response is associated with resistance to a variety of infectious diseases; a Th2 response is associated with disease susceptibility. Because nitrate/nitrite shifted the balance from a Th1 to a Th2 response in some individuals, exposure to these compounds may decrease these persons' responsiveness to infectious diseases. The levels of nitrate used in this study are relevant to human health because they are present in the liquid portion (nonbreastfed) of some 2-month-old infants' diets in rural Romania.
Horizontal and Vertical Distribution of Butyltin Compounds in Sediments from Shipyards in Korea by W. J. Shim; S. H. Hong; U. H. Yim; N. S. Kim; J. R. Oh (pp. 0277-0283).
Butyltin compounds were quantitatively determined in surface sediment and sediment core samples near shipyards in the south coast of Korea, which is one of the major ship building industries in the world. Tributyltin (TBT) concentrations reached up to 46,100 ng Sn/g on a dry-weight basis at the front of the shipyard. Horizontal distribution of butyltin compounds was closely related to dry-docking activities. Butyltin concentrations were relatively low where remote from the sources. The vertical distribution of TBT in sediment cores showed active use of TBT in Korean peninsula for the past decades. The increase of TBT concentrations in sediment core according to estimated sediment age demonstrated a positive correlation with the increase of gross tonnage of ships built in the shipyard for 20 years. High TBT residue levels in sediment core samples raise concerns over persistence of the compound in the marine environment.
Cytogenetic Damage in Shallot (Allium cepa) Root Meristems Induced by Oil Industry “High-Density Brines” by . Vidaković-Cifrek; M. Pavlica; I. Regula; D. Pape (pp. 0284-0291).
Saturated water solutions of calcium chloride, calcium bromide (densities 1.30 kg dm−3 and 1.61 kg dm−3, respectively) and their 1:1 mixture have been commonly used as oil industry “high-density brines.” In our experiment they were added to tap water in amounts appropriate to achieve concentrations of 0.025, 0.05, 0.075, and 0.1 mol dm−3 to study their cytotoxic effect on the root tip cells of shallot (Allium cepa L. var. ascalonicum). All tested solutions in concentrations of 0.075 and 0.1 mol dm−3 caused significant inhibition of shallot root growth. CaBr2 showed this effect in concentration 0.05 mol dm−3. The investigated solutions in all concentrations applied decreased mitotic activity in root tip cells. The most of mitotic abnormalities were the consequence of spindle failure and chromosome stickiness. Furthermore, the cell microtubules were investigated by indirect immunofluorescence to confirm that most abnormalities observed were the consequence of spindle failure. The present study, as well as previously done Lemna tests and Chlorella tests showed that investigated samples have certain effects on plants, so constant control of their presence in the environment is needed.
Comparision of Atrazine and Metolachlor Affinity for Bermudagrass (Cynodon dactylon L.) and Two Soils by M. C. Dozier; S. A. Senseman; D. W. Hoffman; P. A. Baumann (pp. 0292-0295).
Given that bermudagrass is being used as one of the grasses of choice in grass filter strip plantings as an acceptable grass to reduce off-target losses of herbicides, laboratory experiments were conducted to determine and compare the relative affinity of bermudagrass, a Weswood soil, and a Houston Black soil for atrazine (6-chloro-N-ethyl-N-isopropyl-1,3,5-triazine-2,4-diamine) and metolachlor (2-chloro-N-(2-ethyl-6-methylphenyl)–N-(2-methoxy-1-methyethyl) acetamide). Experiments were also conducted to determine if the presence of one herbicide affects the relative affinity of the other compound to these sorbents. The experiments were carried out using radiolabeled atrazine and metolachlor. Results were reported in disintegrations min−1 (dpms) and converted to K d to determine and compare relative affinity. Both K d values for relative affinity of atrazine (86.2) and metolachlor (131.5) to bermudagrass were significantly greater than those of the two soils, Weswood (atrazine, 20.0 and metolachlor, 28.4) and Houston Black (atrazine, 35.8 and metolachlor, 33.5). The two compounds were also mixed together to mimic the common practice of applying atrazine and metolachlor simultaneously as a tank mix. Relative affinity of atrazine to any of the sorbents was not affected by the presence of metolachlor. Similarly, when comparing the affinity of metolachlor alone to that of metolachlor with atrazine present in the solution, no significant differences were observed for bermudagrass or the Weswood soil. However, on the Houston Black soil, the presence of atrazine significantly increased the soil's affinity for metolachlor.
Control of Brackish Water Fouling Mussel, Mytilopsis leucophaeata (Conrad), with Sodium Hypochlorite by S. Rajagopal; M. van der Gaag; G. van der Velde; H. A. Jenner (pp. 0296-0300).
Though the Conrad's false mussel, Mytilopsis leucophaeata, is an important fouling animal in industrial cooling water systems, there are no published reports on the tolerance of this species to chlorination. A series of experiments was conducted to determine the effects of mussel size (2–20 mm shell length), season (breeding versus nonbreeding), nutritional status (fed versus starved) and acclimation temperature (5–30°C) on the mortality pattern of M. leucophaeata under continuous chlorination (0.25–5 mg/L). The effect of mussel size on M. leucophaeata mortality in the presence of chlorine was significant, with 10 mm size group mussels showing greater resistance. At 0.25 mg/L residual chlorine, 2 mm size group mussels took 89 days to reach 100% mortality, whereas 10 mm size group mussels took 109 days. M. leucophaeata collected during nonbreeding season (December–April) was more tolerant to chlorine than those collected during breeding season (June–October). Nutritional status of the mussel had no significant influence on the chlorine tolerance of the mussel: fed and starved mussels succumbed to chlorine at equal rates. The effect of acclimation temperature on M. leucophaeata mortality in the presence of chlorine was significant. At 0.5 mg/L residual chlorine, mussels acclimated at 5°C required 99 days to reach 95% mortality, whereas mussels acclimated at 30°C required 47 days. A comparison of present data with previous reports suggests that resistance of M. leucophaeata to chlorination is higher than other mussel species causing fouling problems in The Netherlands (Mytilus edulis and Dreissena polymorpha).
Metal Concentrations in Zebra Mussels and Sediments from Embayments and Riverine Environments of Eastern Lake Erie, Southern Lake Ontario, and the Niagara River by T. P. Lowe; D. D. Day (pp. 0301-0308).
Concentrations of 14 metals were studied in the soft tissues of zebra mussels (Dreissena polymorpha) and sediments from 16 Great Lakes embayments and riverine environments. Samples were collected in 1993 and 1994 during the early and late autumn period when the body mass of mussels is least affected by reproductive activities. There was a significant difference in geometric mean concentrations of all metals except Cu in mussels sampled from different sites, and there was a significant difference in the geometric mean concentrations of all metals but Cd, Mn, and Zn between years. The higher metal concentrations in mussels from this study were generally similar to those in mussels from contaminated European and U.S. locations, and those with lower concentrations were similar to those from uncontaminated European and U.S. locations. Geometric mean sediment concentrations of all metals differed significantly among sites. Sediment concentrations of metals from some sites were above EPA guidelines for moderately polluted harbor sediments. Sites where zebra mussels had higher concentrations of Al, Cr, and V tended to be the same sites as those where sediment concentrations of these metals were also higher. However, there was not a significant statistical relationship between concentrations of metals in zebra mussels and sediments, except for Mg.
Mercury Concentrations in Fish from Lake Mead, USA, Related to Fish Size, Condition, Trophic Level, Location, and Consumption Risk by J. V. Cizdziel; T. A. Hinners; J. E. Pollard; E. M. Heithmar; C. L. Cross (pp. 0309-0317).
Total mercury (Hg) concentrations were determined in the skeletal muscle of 339 fish collected during the fall of 1998 and spring of 1999 from Lake Mead, USA, the nation's largest human-made reservoir. Five species of fish representing a range of trophic levels and the lake's principal game fishes were studied. Hg generally increased with trophic level and fish size. Median Hg concentrations (ng/g wet mass) were 277 in striped bass, 168 in channel catfish, 160 in largemouth bass, 75 in bluegill, and 8 in blue tilapia. Overall, fish from Las Vegas Bay and Boulder Basin had the lowest Hg concentrations, possibly a result of biodilution in this biologically productive area. In general, fish-mercury advisories might include a warning about consuming fillet from emaciated fish, based on the finding that Hg concentrations in 59 striped bass (captured during a scarce-food season) correlated inversely (r = −0.89, p < 0.001) with a fish nutritional-status factor. This is consistent with starvation-concentration, whereby Hg in fish muscle is lost at a slower rate than the muscle mass. The median concentration found for 139 striped bass corresponds to a recommended risk-based consumption limit of three 8-oz. (227-g) meals per month for a 70-kg adult. Finally, this paper serves as a useful archive for future research and long-term studies of Hg in Lake Mead fish.
Northern Bobwhite and Lead Shot Deposition in an Upland Habitat by M. K. Keel; W. R. Davidson; G. L. Doster; L. A. Lewis (pp. 0318-0322).
We estimated total lead shotshell pellets expended, resultant pellet availability near soil surface, and the frequency of pellet ingestion by northern bobwhites (Colinus virginianus) attributable to nearly a quarter century of bobwhite hunting on a 202-ha upland habitat at Tall Timbers Research Station, Leon County, Florida. A total of 7,776 shots were fired, resulting in the expenditure of approximately 4.5 million pellets (∼ 22,519/ha). Sixteen of 235 (6.8%) soil samples collected in 1989 and 1992 contained one or two pellets. Soil samples indicated that approximately 7,800 pellets/ha (about 35% of the projected 24-year deposition) were within 2.54 cm of the soil surface. Pellet ingestion by bobwhites was evaluated by examining 241 gizzards collected from 1989–92. Three bobwhites (1.3%) had ingested pellets (x¯ = 1.3 pellets). No instances of suspected lead poisoning were noted in bobwhites over the 24-year period. Sport hunting of wild bobwhite populations on upland habitats appears to produce a low potential for lead poisoning compared to lead deposition in association with waterfowl and dove hunting.
Inter- and Intraclutch Variability in Heavy Metals in Feathers of Great Tit Nestlings (Parus major) Along a Pollution Gradient by E. Janssens; T. Dauwe; L. Bervoets; M. Eens (pp. 0323-0329).
Heavy metal (silver, arsenic, cadmium, copper, mercury, lead, and zinc) concentrations were analyzed in feathers of nestling great tits (Parus major) collected along a pollution gradient. Differences in metal concentrations along the gradient and inter- and intraclutch variability were investigated. In the immediate vicinity of the pollution source, feathers of nestling great tits contained significantly higher concentrations of silver, arsenic, mercury, and lead than at the sites further along the gradient. The concentrations of copper and zinc, two essential metals, were significantly lower at the second most polluted site. There was no significant difference in cadmium concentrations among sites. Most metals, except cadmium, were significantly positively correlated with each other. There was a significant amount of interclutch variability in feather metal concentrations, and they differed significantly among sites. The amount of inter- and intraclutch variability did not differ significantly, although intraclutch variability of most metals was markedly high. Our study indicates that feathers of great tit nestlings could be used as bioindicators of metal pollution, but attention should be paid in designing representative sampling procedures.
Effects of Phos-Chek G75-F and Silv-Ex on Developing Northern Bobwhite Quail (Colinus virginianus) by D. M. Buscemi; D. J. Hoffman; N. B. Vyas; J. W. Spann; W. J. Kuenzel (pp. 0330-0337).
Eggs of nesting birds situated in peripheral areas serving as fire breaks are at risk of being sprayed with fire control chemicals. Acute toxicity tests were conducted by immersing northern bobwhite quail eggs for 10 s in different water-based concentrations of Silv-Ex® (SE), a foam-suppressant chemical, and Phos-Chek® G75-F (PC), a fire retardant chemical, on day 4 or day 11 of incubation. An attempt was made to relate the treatment concentrations to the actual field application levels. Mortality appeared higher in most groups exposed on day 11 than on day 4, suggesting that on day 11 the extensive chorioallantoic vascular network permitted greater uptake of chemical. Only 24–60% of the embryos survived to hatch at exposure concentrations of 202, 269, and 454 g/L PC when treated on incubation day 11. At higher concentrations including 681, 956, and 1,211 g/L PC, the compound did not completely dissolve in water and clumped on eggshells, resulting in greater hatching success. Exposures to SE at 100 g/L on incubation day 11 did not significantly affect hatching success of embryos but did significantly reduce the percent hematocrit in blood compared with controls. Incubation day 11 exposure to 202 and 1,211 g/L PC led to a significant increase in plasma aspartate aminotransferase, and day 4 exposure to 1,211 g/L PC resulted in a significant increase in alanine aminotransferase. In addition to elevated liver enzymes, these treatments resulted in a decrease in the number of hepatocyte profiles (1,211 g/L PC at day 4 and day 11) and an increase in hepatocyte size (202 and 1,211 g/L PC at day 11) in hatchlings. A combination of SE and PC was synergistic (202 g/L PC and 50 g/L SE) at day 11 of incubation with respect to decreased hatching success and reduced bone lengths. However, lower concentrations of SE (10 g/L or 30 g/L) combined with 202 g/L of PC appeared antagonistic. This may be due to SE, as a surfactant, altering the ability of PC to penetrate the egg. Our results show fewer adverse effects following exposure to SE than to PC; therefore application of SE may be less harmful to breeding bird populations.
Thyroid Hormone Suppression and Cell-Mediated Immunomodulation in American Kestrels (Falco sparverius) Exposed to PCBs by J. E. Smits; K. J. Fernie; G. R. Bortolotti; T. A. Marchant (pp. 0338-0344).
Exposure to environmental contaminants can induce physiological changes in animals through various mechanisms. One manifestation of subclinical toxicity from polychlorinated biphenyl (PCB) exposure is the disruption of normal immune function described in numerous species, including American kestrels (Falco sparverius). In 1998, 152 mature male and female kestrels were fed either a mixture of Aroclor 1248:1254:1260 (approximately 7 mg/kg kestrel/day) through their food items, or control diets. Offspring produced by 50 breeding pairs (thus, half received in ovo PCB exposure only) were also studied. Total and differential white blood cell counts, the phytohemagglutinin (PHA) skin response, as well as thyroid hormone levels were tested in vivo in nonbreeding adults (1998 only) and nestlings (1998 and 1999). In 1999, nestlings came from three parental groups; adults exposed in 1998, birds produced by PCB-exposed parents, and unexposed birds. In 1998, directly exposed males but not females had increased total white blood cell counts driven by lymphocytosis, plus a decreased heterophil-to-lymphocyte ratio relative to controls. PCB-exposed birds had a significantly greater response to PHA than did controls, with sex as a significant factor and plasma triiodothyonine (T3) as a significant covariate. Levels of T3 were significantly depressed in PCB-exposed birds of both sexes. The 1999 nestlings (F1 generation with respect to PCB exposure) did not show any effect of parental treatment group on the PHA skin response, yet T3 remained as a significant covariate. Immunological effects are discussed in light of the antibody-mediated immunotoxicity found in the same birds and reported previously.
Lack of a Distinct Gradient in Biomarker Responses in Small Mammals Collected at Different Distances from a Highway by T. Hamers; L. A. M. Smit; A. T. C. Bosveld; J. H. J. van den Berg; J. H. Koeman; F. J. van Schooten; A. J. Murk (pp. 0345-0355).
This study describes biomarker effects in small mammals exposed to traffic emissions. Animals were collected at 10–50 m (site 1), 150–200 m (site 2), and 5 km (site 3) from a very busy highway (A2). To distinguish between routes of exposure, strictly carnivorous common shrews (Sorex araneus) and predominantly herbivorous bank voles (Clethrionomys glareolus) were collected. As a measure of exposure to polycyclic aromatic hydrocarbons (PAHs), aromatic DNA adduct levels were determined by 32P-postlabeling techniques in tissue from heart, lung, and liver. Lead (Pb), cadmium (Cd), and copper (Cu) levels were analyzed in kidney as a measure of exposure to heavy metals. EROD and PROD activity and retinoid levels were determined in liver as effect biomarkers for exposure to PAHs and polyhalogenated aromatic hydrocarbons (PHAHs). Relatively high Cd levels in S. araneus and in particular elevated DNA adduct levels in C. glareolus indicated that small mammals at site 3 were exposed to more compounds than at sites 1 and 2 (3 ≥ 1 > 2). The latter effect is probably due to an incidental and actual input of airborne pollutants that is deposited on plant surfaces. By consumption of above-ground vegetation, voles are chronically exposed to this pollution. Relatively high background input of PAHs probably hinders that the traffic-related gradient of airborne PAH concentrations found in an earlier study is reflected in DNA adduct levels in small mammals in the present study. Moreover, historical biomarkers for exposure to traffic emissions, such as increased kidney Pb levels, increased hepatic EROD activity, and disturbed hepatic vitamin A homeostasis are no longer applicable to indicate differences in exposure. This is a result of the ban on addition of Pb and chlorinated scavengers to gasoline and of cleaner combustion techniques, which were enforced by law over the past decade. Finally, it is advisable to use only juvenile small mammals for in situ monitoring of diffuse pollution because DNA adduct levels increased with age.
Raccoon (Procyon lotor) as a Bioindicator of Mercury Contamination at the U.S. Department of Energy's Savannah River Site by C. G. Lord; K. F. Gaines; C. S. Boring; I. L. Brisbin, Jr.; M. Gochfeld; J. Burger (pp. 0356-0363).
Raccoons (n = 95) were collected from the U.S. Department of Energy's Savannah River Site (SRS) and from public hunting areas. Raccoons were collected near a stream drainage system (Steel Creek delta) and a former reactor-cooling reservoir (pond B) that received inputs of mercury-contaminated Savannah River water. Mercury concentrations were determined for hair, liver, kidney, muscle, and spleen tissues. Samples were analyzed using inductively coupled plasma mass spectroscopy (ICP-MS) and cold vapor atomic absorption spectroscopy (CVAAS). Raccoons were also collected from a natural stream floodplain system (Upper Three Runs/Tinker Creek) located upstream of Hg use and storage areas and near coal ash basins. These samples were compared to samples collected from off-site hunting areas near the SRS. Hg concentrations between internal tissues were significantly correlated. Hair did not correlate well with internal tissue and was a weak indicator of raccoon exposure to Hg. Nonetheless, raccoons are potentially good indicators of Hg contamination because tissue concentrations were higher in raccoons from areas with known Hg input than in those from reference areas, and muscle biopsies can be used as biomarkers for contaminant exposure. Muscle Hg concentrations ranged from 0–0.14 ppm from nearby hunting grounds, indicating that people hunting in designated areas near the SRS are at negligible risk for Hg consumption from raccoon meat. Several raccoons collected from the SRS had muscle Hg concentrations at or near the FDA action level for seizing commercial fish due to mercury contamination of 1.0 ppm. Though Hg action levels for wild game have not been proposed, it is clear that some SRS raccoons had Hg levels that warrant concern if these areas would be open to public hunting. Last, 64 raccoons from this study had Hg concentrations that were considered elevated by the U.S. FWS standard (> 1.1 ppm) of ecosystem health for one or two tissues (hair, liver, or kidney), and 17 had high concentrations for most or all tissues.
Organochlorine Hydrocarbons in Human Breast Milk Collected in Hong Kong and Guangzhou by C. K. C. Wong; K. M. Leung; B. H. T. Poon; C. Y. Lan; M. H. Wong (pp. 0364-0372).
In southern China, the awareness of persistent organic pollutant contamination has been increasing as a considerable number of past studies in Hong Kong had reported their trail in the coastal sediments, green-lipped mussels, muscle and viscera of pond fish, and foodstuffs. Hence there is an urgent need to assess their existence, contamination profiles, and potential impact on the public. In the present study, a survey was conducted to examine p,p′-DDT, p,p′-DDE, β-HCH, and PCB concentrations in human breast milk, one of the most reliable bioaccumulation indicators. Milk samples (115 from Hong Kong and 54 from Guangzhou), in the lactation period from 3–5 weeks were analyzed. The results demonstrated that the mean levels of p,p′-DDT (Hong Kong: 0.39; Guangzhou: 0.70 μg/g of fat), p,p′-DDE (2.48; 2.85), and β-HCH (0.95; 1.11) were 2–15-fold higher when compared with studies conducted elsewhere (i.e., United Kingdom, Germany, Sweden, Spain, and Canada), and in contrast the concentration of PCBs (0.035; 0.031) was about 10 times lower. When compared to a similar study conducted 10 years ago in Hong Kong (p,p′-DDT 2.17 μg/g of fat, p,p′-DDE 11.67, β-HCH 15.96, and PCB 0.64), a considerable reduction in the levels of their contaminations was observed. The drastic reduction in body burdens in 10 years' time is presumably the result of effective regulatory actions. It is worth noting that body burden correlated positively with maternal age (total DDT, r = 0.93; β-HCH, r = 0.91; PCBs, r = 0.77) and with historical record of seafood consumption (total DDT, r = 0.89; β-HCH, r = 0.98; PCBs, r = 0.91) (p < 0.001) and potential uptake of the POPs by breastfed infants may pose adverse health hazards.
Determining Demographic Effects of Cypermethrin in the Marine Copepod Acartia tonsa: Stage-Specific Short Tests Versus Life-Table Tests by C. Barata; M. Medina; T. Telfer; D. J. Baird (pp. 0373-0378).
Short-term lethal and sublethal responses of the calanoid copepod Acartia tonsa to cypermethrin were compared with life-table responses to assess whether or not it is necessary to use exposure periods longer than 5 days to estimate demographic responses to stress. More specifically, by limiting exposure periods to sensitive age classes (eggs, nauplii, copepodids, and adults) and including measurements on survival, egg production, and feeding rates, it was possible to derive a short test design of similar sensitivity and ecological relevance as full life-table tests. Short-term exposures to cypermethrin reduced copepodid's feeding rates at concentrations well below those affecting egg production rates and survival of eggs and adult stages. Lethal effects on naupliar stages occurred at lower concentrations than any other effect observed on eggs and adults. Life-table sensitivities of the intrinsic rate of increase (r m) to cypermethrin were similar to those observed in short-term exposures. More specifically, exposure to cypermethrin impaired r m responses at concentrations (7.4 ng L−1) that also affected feeding and naupliar responses. Our results show that by quantifying and separating combined toxic effects on ecologically relevant individual life-history traits, it is possible to develop toxicity test designs of similar ecological relevance yet that are less labor-intensive and costly than existing demographic tests.