Robert J. Huggett

Induced cytochrome P-450 in intestine and liver of spot (Leiostomus xanthurus) from a polycyclic aromatic hydrocarbon contaminated environment

Abstract Levels of total cytochrome P-450, of specific P-450 (determined immunologically with MAb 1-12-3 and referred to as P-450E) and ethoxyresorufin O-deethylase (EROD) were elevated in intestine and liver microsomes of spot (Leiostomus xanthurus) collected from the Elizabeth River, a polycyclic aromatic hydrocarbon (PAH) contaminated tributary of Chesapeake Bay. Fish were collected over a sediment PAH concentration gradient that ranged from 9 to 96 000 μg PAH/kg dry sediment. Intestinal P-450E was near the lower limits of detection in fish collected at the relatively clean sites but was elevated 80- to 100-fold in fish collected from contaminated sites. Intestinal EROD activity exhibited a similar trend. Liver P-450E and associated EROD activity was detectable in all samples and was induced approximately eight-fold at the most heavily contaminated site. Despite the sensitivity of the intestine to PAH inducing agents, intestinal P-450E levels did not correlate well with sediment PAH, whereas liver P-450E did. Instead, the intestinal enzyme was induced to similar and high levels at all contaminated sites. The results suggest that the intestine plays an important role in the absorption and metabolism of dietary PAH and/or other PAH-type inducing agents and that intestinal P-450E may be a useful indicator of exposure to these compounds via the diet.

GC determination of butyltins in natural waters by flame photometric detection of hexyl derivatives with mass spectrometric confirmation

Abstract Butyltin compounds in the 1–100 ng Sn/Liter range are solvent extracted from estuarine waters and derivatized with n-hexyl magnesium bromide. This forms tetraalkyltins that are quantified by gas chromatography with flame photometric detection and confirmed by gas chromatography mass spectrometry. The n-hexyl derivatives of methyltin and butyltin species are easily separated, and quantified relative to an internal standard, tripentyltin chloride.

Polycyclic Aromatic Hydrocarbons in Surface Sedicments from the Elizabeth River Subesturary

Abstract The concentration and nature of mainly aromatic and polar organic compounds in surface sediments form the Elizabeth River was assessed in 28 samples, using methodlology combining simplicity and reliability so that it scould be applied in a quasi routine fashion. The analyses reveal unsubstituted polynuclear aromatic hydrocarbons (PAHs) as major components of these sediments, indicating an origin form high temperature processes. The conspicuous absence of cyclopenta (c,d)pyrene in these samples is characteristic of an origin form coal. Concentrations of PAHs were highest in the Southern Branch of the Elizabeth River, where the sum of 14 generally abundant pyrogenic PAHs in one sample was 170 ppm and could be traced to two massive spills of wood preservatives. This maximum concentration decreases exponentially towards the mouth of the river with a correlation coefficient of -0.92 and fits a diffusion-advection model for -k/w=3.5km. The physcial details of the processes dispersing these PAHs are not...

Equilibrium Sorption of Tributyltin Chloride by Chesapeake Bay Sediments

Sorption of tributyltin chloride (TBT) on selected sediments from Chesapeake Bay and its tributaries has been measured to establish ranges for TBT sorption coefficients. Twenty-four hour sorption isotherms were linear and gave sorption coefficients on the order of10^{3}. Twenty-four hour desorption isotherms indicate that the sorption is reversible. To examine the dependence of TBT sorption on salinity, sediment was equilibrated with TBT solutions that spanned estuarine salinity conditions. The resulting sorption coefficients decreased with increasing salinity and varied by a factor of two over the salinity range.

Organic compounds in Chesapeake Bay sediments

Abstract The concentrations of organic compounds in bottom sediments from the main stem of the Chesapeake Bay are reviewed. In all stations listed in this paper, a few distinct polynuclear aromatic hydrocarbons (PAH) are present at much higher concentrations than other organic compounds. There is a general trend in concentrations of these PAH decreasing from north to south. This likely reflects the higher human population density in the northern region. Over the time period of 1979 to 1986, the levels of polynuclear aromatic hydrocarbons have remained relatively constant at the stations considered in this manuscript.

Statistical modeling of intensive TBT monitoring data in two tidal creeks of the Chesapeake Bay

Abstract Results are presented from a three year program of weekly tributyltin (TBT) monitoring at nine stations in two tidal creeks of the Chesapeake Bay. Most stations are near dense moorings of recreational boats. The logarithm of TBT + concentration is shown to have appropriate statistical and mathematical properties for modeling. All stations with a relatively high concentration of TBT + (> 10 ng/liter) show a significant annual variation superimposed upon a decreasing linear trend. The trend slope corresponds to a half-life of about 2–3 years. There is strong evidence that the model residuals are uncorrelated in time. All the high concentration stations in a creek system can be adequately modeled by the same annual component amplitude and phase values and the same linear trend slope, while individual stations differ only in overall concentration.

Mercury in sediments from three Virginia estuaries

A survey of mercury levels in sediments (<63 μ) from Virginias three main estuaries was conducted. Results indicated that the mercury was associated with the organic fraction of the bottom material. Statistical analyses showed no differences (5% significance level) within rivers with respect to distance from the mouth or between rivers.

Polynuclear Aromatic Hydrocarbon Residues in Shellfish: Species Variations and Apparent Intraspecific Differences

Concern over the occurrence of polynuclear aromatic hydrocarbons residues (PAHs) in marine animals originates from two areas. The first relate to the potential effects of these substances on the biota, and the second arises from the transfer of the residues to higher animals, e.g., man. Several authors including: Malins and Hodgins (12), Mix (13), Hargis and Roberts (5), and Huggett et al. (7), have implicated PAHs as being the causative factors in various diseases and/or abnormalities of marine animals. Howard and Fazio (6) reviewed the occurrence of PAHs in a variety of foods and Neff (14) summarized the information on PAHs in aquatic environments. However, Neff observed in 1979, that “comparatively little information is available concerning the presence of PAHs other than BaP [benzo(a)pyrene] or concerning the PAH homolog distribution in tissues of aquatic organisms”. This paper provides updated information on these subjects from the recent literature and through original observations.

Polynuclear Aromatic Hydrocarbon Monitoring in Estuaries Utilizing: Oysters, Brackish Water Clams and Sediments

The monitoring of contamination from polynuclear aromatic hydrocarbons (PAH) in estuarine animals is complicated by the necessity of utilizing different species as one progresses upstream along the salinity gradient. In the Chesapeake Bay, most tributary sub-estuaries contain two bivalve species, the oyster, Crassostrea virginica, and the brackish water clam, Rangia cuneata, which frequently have overlapping distributions. This paper describes the use of these species and sediments as monitors for PAH contamination in the James, York and Rappahannock rivers. Seasonal, species and source related differences are discussed.

The suspended sediment-water partitioning coefficient for kepone® in the James River, Virginia

Abstract Field work in the James River, Virginia, showed the suspended sediment-water partitioning coefficient for Kepone to be approximately 5 × 10 3 . This verifies a previous laboratory estimate. The coefficient appears to be independent of salinity and suspended sediment concentration and was not affected by tropical storm David. Evidence suggests that the main effect of the storm was the flushing of some Kepone from the river.