Bioaccumulation and Chronic Toxicity of Bis(tributyltin) Oxide (TBTO): Tests with a Saltwater Fish

Abstract

The accumulation and depuration of bis(tributyltin) oxide (TBTO), a widely used active ingredient in antifouling paints, and its acute and chronic toxicity to sheepshead minnows (Cyprinodon variegatus) were determined. Equilibrium between the concentration of carbon-14-labeled-TBTO in seawater and in fish tissues was not reached after 58 days of exposure. The maximum observed bioconcentration factor in whole fish was ×2600. The maximum observed bioconcentration factors for the muscle, viscera, and remains were ×1810, ×4580, and ×2120, respectively. Sheepshead minnows depurated 52 percent of the 14C-TBTO within 7 days and 74 percent after 28 days. The 21-day median lethal concentration (LC50) for sheepshead minnows exposed to TBTO was 0.96 ppb. The only statistically significant effect observed in the life-cycle test was mortality of the F0 fish in the mean measured TBTO concentration of 4.8 ppb. There was an obvious concentration-response relationship in mortality of the F1 fish, although, no statistically significant differences in mortality were detected between the control and the TBTO-exposed treatments. The surviving F1 fish exhibited no signs of abnormal development, nor was growth decreased as a result of F0 exposure to TBTO concentrations <-1.0 ppb. Tissue samples from the life-cycle test, analyzed for total tin, confirmed the bioconcentration of TBTO, showed the accumulation to be concentration dependent, and indicated that the fish were actively metabolizing TBTO into its lower and less toxic alkyl moieties.

Comparison of imposex and intersex development in four prosobranch species for TBT monitoring of a southern European estuarine system (Ria de Aveiro, NW Portugal)

“…A portion of the surficial layer (1 cm) of the sediment was removed with a spatula, at about the mid-tide level, placed in a polyethylene bag and deep frozen (-20°C) for storage. Homogenised wet unsieved sub-samples were analysed for TBT following the methods based on Ward et al (1981) that are fully described by Bryan et al (1986), rendering a detection limit of about 5 ng Sn g -1 dry weight (DW). The moisture content was determined from a separate aliquot.…”

Imposex levels and tributyltin pollution in Ria de Aveiro (NW Portugal) between 1997 and 2007: evaluation of legislation effectiveness

“…Although this technique does not perform the complete OTs speciation (of butyl-, phenyl-and octyltins), previous studies have shown that butyltins (BTs) represent the dominant OT fraction in the study area and, of these, TBT is the most abundant compound. [19][20][21] Analytical procedures were largely based on those of Ward et al 22 as modified and described fully by Bryan et al 8 Recoveries of TBT and DBT were $100 and 92% respectively, and were corrected by the use of standard additions in all samples. Detection limits for TBT and DBT were about 10 ng Sn g À1 dw.…”

Organotin contamination, imposex and androgen/oestrogen ratios in natural populations of Nassarius reticulatus along a ship density gradient

“…The samples collected in 1997 were analysed for TBT and dibutyltin (DBT) using methods described in detail elsewhere. 11,12 Briefly, four to six frozen specimens (separated by sex) were pooled and then homogenized. Two replicates of tissues were taken for analysis.…”