Seasonal concentrations of organic contaminants at the fall line of the Susquehanna River basin and estimated fluxes to northern Chesapeake Bay, USA

Abstract

Riverine fluxes of several pesticides and other organic contaminants from above the fall line of the Susquehanna River basin to northern Chesapeake Bay, USA, were quantified in 1994. Base flow and storm flow samples collected at the fall line of the river from February to December 1994 were analyzed for both dissolved and particulate phase contaminants. Measured concentrations of the organonitrogen and organophosphorus pesticides varied mainly in response to the timing of their application to agricultural fields. Conversely, the concentrations of the more particle‐sorptive contaminants such as polychlorinated biphenyls (PCBs), organochlorine (OC) insecticides, and polycyclic aromatic hydrocarbons (PAHs) were more directly correlated with river flow throughout the year. Annual fluxes were almost entirely in the dissolved phase for the organonitrogen and organophosphorus pesticides, distributed between the dissolved and particulate phases for the PCBs and OC insecticides, and primarily in the particulate phase for the PAHs.

Concentrations and loads of PCBs, dioxins, PAHs, PBDEs, OC pesticides and pyrethroids during storm and low flow conditions in a small urban semi-arid watershed

“…PAH loading is approximately 100-fold greater than the next highest class (pyrethroids), yet conceptually ranks appropriately among the yields reported for other types of watersheds (e.g. the Z4LA yield was less than reported by Smith et al (2000) for four targeted traffic and gas station land use drainage areas in Virginia (32.3-2240 mg/m 2 /y), greater than reported for the very large, rurally dominated Susquehanna River (0.069 mg/m 2 /y: Foster et al, 2000a), and similar to the predominantly urban Anacostia River watershed (1.7 mg/m 2 /y; Foster et al, 2000b)). …”

“…Although highly urbanized, the Z4LA watershed contains no known PCB source areas; PCB transport in this watershed is likely more generally representative of older mixed urban and industrial land uses. In contrast, watersheds with known specific industrial sources appear to exhibit average concentrations in excess of about 100 ng/l (Hwang and Foster, 2008;Marsalek and Ng, 1989;McKee et al, 2012;Zgheib et al, 2011Zgheib et al, , 2012 and watersheds with little to no urbanization dominated by agriculture and open space exhibit average concentrations b5 ng/l (David et al, 2015;Foster et al, 2000a;Howell et al, 2011;McKee et al, 2012) (see Supplementary Information Figure S3). …”

“…Runoff of these toxic and persistent chlorinated organic compounds to the local Bay Area tributaries is estimated to comprise a significant portion of the loading estimated N 9-15 kg/year was sourced from urban tributaries). PCBs have been relatively well studied in urban runoff in other areas of the world (Foster et al, 2000a(Foster et al, , 2000bHwang and Foster, 2008;Rossi et al, 2004;Howell et al, 2011;Zgheib et al, 2011Zgheib et al, , 2012 and concentrations appear to be the greatest in watersheds with older (pre-1980) industrial areas (McKee et al, 2012). PCBs have been found to occur dominantly in particulate phase (Hwang and Foster, 2008;Zgheib et al, 2011) and the degree of partitioning appears to relate to the degree of chlorination (Tlili et al, 2012).…”

Elevated whole brain arginine vasotocin with Aroclor 1254 exposure in two Syngnathus pipefishes

“…The PCB exposure including study rationale, exposure procedure, and analytical confirmation of concentration are documented in Ripley and Foran (2008). Briefly, Aroclor 1254 was selected based on documented widespread prevalence in Chesapeake Bay water, sediment, and organisms and its listing among toxicants of concern for this region (Ashley and Baker 1999;Foster et al 2000). Males were introduced to the exposure study immediately following laboratory mating and identification of brooding.…”

“…The lipophilic PCB had to be dissolved in a solvent for the water exposure; accordingly, two treatment groups were established: acetone, or vehicle, control, and 53 lg l -1 Aroclor 1254 (Ultra Scientific, North Kingstown, RI, USA). As the purpose of the Ripley and Foran (2008) study was to investigate the sensitivity of parental nutrient allocation to this environmental contaminant and not to construct a dose-response curve, only one, midrange environmental concentration of Aroclor 1254 was tested and only post-brooding males were considered (Ashley and Baker 1999;Foster et al 2000). Brooding males were held individually in 4 L of 25 ppt artificial salt water (Instant Ocean, Mentor, OH, USA) in an ENCONAIR ecological chamber (Winnipeg, Canada; model GC-16) at 24 ± 1°C on a 14:10 h light:dark cycle (on 6:00 h: off 20:00 h) until fry release.…”