PFOA, PFOS and PFHxS toxicokinetic considerations for the development of an in vivo approach for assessing PFAS relative bioavailability in soil.

A Sprague-Dawley rat model was utilized to elucidate perfluorooctanoic acid (PFOA), perfluorooctanesulfonic acid (PFOS) and perfluorohexanesulfonic acid (PFHxS) toxicokinetics with a goal of developing an in vivo approach for quantifying PFAS relative bioavailability in impacted soil. Following single dose administration (gavage) of ∼ 0.2-2000 µg kg BW of PFOA, PFOS or PFHxS, differences in PFAS blood, organ and excreta concentrations were observed over 120 h although linear dose responses were determined for area under the blood plasma time curves (AUC; PFOA, PFHxS), liver accumulation (LA: PFOS) and urinary excretion (UE; PFOA, PFHxS).

Soil amendments reduce PFAS bioaccumulation in Eisenia fetida following exposure to AFFF-impacted soil.

The efficacy of RemBind® 300 to immobilize per- and polyfluoroalkyl substances (PFAS) in aqueous film forming foam (AFFF)-impacted soil (∑ PFAS 1280-8130 ng g; n = 8) was assessed using leachability (ASLP) and bioaccumulation (Eisenia fetida) endpoints as the measure of efficacy. In unamended soil, ∑ PFAS leachability ranged from 26.0 to 235 μg l, however, following the addition of 5% w/w RemBind® 300, ∑ PFAS leachability was reduced by > 99%.

Acute toxicity of the insecticide methyl parathion and its hydrolytic product p-nitrophenol to the native Australian cladoceran Daphnia carinata.

The toxicity of an organophosphorus (OP) insecticide, methyl parathion (MP), and its hydrolysis product, p-nitrophenol (PNP), to the native Australian cladoceran species, Daphnia carinata, was assessed. Both MP and PNP were stable in cladoceran water during the test period. D.

Sorption of C-carbofuran in Austrian soils: evaluation of fate and transport of carbofuran in temperate regions.

Carbofuran is an anticholinesterase carbamate commonly used as an insecticide, nematicide and acaricide in agricultural practice throughout the world. However, data on its sorption in temperate soils from Europe is limited. Laboratory studies were conducted to determine the adsorption of carbofuran on three distinct Austrian soils using batch experiments and radiometric techniques.

Sorption and mobility of C-fenamiphos in Brazilian soils.

Although fenamiphos is widely used as an insecticide and nematicide in bowling greens and agriculture, information on its sorption in tropical soils is limited. In this study, mobility, sorption, and desorption dynamics of C-fenamiphos in three contrasting Brazilian soils were examined both in batch and column experiments. Fenamiphos sorption coefficients (K ) were 2.

Toxicity and transformation of insecticide fenamiphos to the earthworm Eisenia fetida.

This study was conducted to investigate the toxicity of the organophosphate insecticide fenamiphos to earthworms (Eisenia fetida) under laboratory conditions. Earthworms were exposed to soils differing in their physico-chemical properties spiked with fenamiphos at concentrations ranging from 10 to 200 mg kg(-1) for a period of 4 weeks. Residues of fenamiphos and its metabolites were determined in both soils and earthworms after 4 weeks of pesticide exposure.

Fenamiphos and related organophosphorus pesticides: environmental fate and toxicology.

In this review, we emphasize recent research on the fate, transport, and metabolism of tree selected organophosphorus pesticides (fenamiphos, isofenphos, and coumaphos) in soil an water environments. This review is also concerned with the side effects of these pesticides on nontarget organisms. Despite the fact that fenamiphos is not very mobile, its oxides have been detected in the groundwaters of Western Australia.

Hydrolysis of fenamiphos and its toxic oxidation products by Microbacterium sp. in pure culture and groundwater.

A bacterium with an exceptional ability to hydrolyse fenamiphos and its toxic oxidation products fenamiphos sulfoxide and fenamiphos sulfone, all possessing POC bond was isolated from soil. Based on 16S rRNA gene determination, this bacterium was putatively identified as Microbacterium esteraromaticum. The phenols (fenamiphos phenol, sulfoxide phenol and sulfone phenol) formed during bacterial hydrolysis resisted further degradation in mineral salts medium and sterile groundwater, but were transitory in non-sterile groundwater due to the catabolism of native microorganisms.

Effect of insecticide fenamiphos on soil microbial activities in Australian and Ecuadorean soils.

The effect of fenamiphos, a widely used organophosphorus pesticide, on important soil microbial activities such as dehydrogenase, urease and potential nitrification in four soils from Australia and Ecuador were studied. The results showed fenamiphos in general was not toxic to dehydrogenase and urease up to 100 mg/Kg soil. However potential nitrification was found to be highly sensitive to fenamiphos with a significant inhibition recorded even at 10 mg/Kg soil.

Biodegradation of the pesticide fenamiphos by ten different species of green algae and cyanobacteria.

The degradation of an organophosphorus pesticide, fenamiphos, by different species of five green algae and five cyanobacteria was studied. All the species tested were able to transform fenamiphos to its primary oxidation product, fenamiphos sulfoxide (FSO), while the majority of these cultures were able to hydrolyze FSO to fenamiphos sulfoxide phenol (FSOP). Fenamiphos sulfone phenol, FSOP, and FSO were detected in the culture extracts of these algae and cyanobacteria.

Sorption of fenamiphos to different soils: the influence of soil properties.

Fenamiphos (0-ethyl-0(3-methyl-4-methylthiophenyl)-isopropylamido-phosphate) is a widely used nematicide and insecticide in bowling greens and agriculture, but information on its sorption including its metabolites is limited. Hence, the sorption of fenamiphos (nematicide) and its major degradation products fenamiphos sulfoxide (FSO) and fenamiphos sulfone (FSO2) were determined in thirteen contrasting soils collected from Australia and Ecuador. The sorption coefficients (Kd) exhibited a wide range of variation from 2.

Toxicity and transformation of fenamiphos and its metabolites by two micro algae Pseudokirchneriella subcapitata and Chlorococcum sp.

The acute toxicity of an organophosphorous pesticide, fenamiphos and its metabolites, fenamiphos sulfoxide (FSO), fenamiphos sulfone (FSO(2)), fenamiphos phenol (FP), fenamiphos sulfoxide phenol (FSOP) and fenamiphos sulfone phenol (FSO(2)P), to the aquatic alga Pseudokirchneriella subcapitata and the terrestrial alga Chlorococcum sp. was studied. The toxicity followed the order: fenamiphos phenol>fenamiphos sulfone phenol>fenamiphos sulfoxide phenol>fenamiphos.

Degradation of fenamiphos in soils collected from different geographical regions: the influence of soil properties and climatic conditions.

The persistence of fenamiphos (nematicide) in five soils collected from different geographical regions such as Australia, Ecuador and India under three temperature regimes (18, 25 and 37 degrees C) simulating typical environmental conditions was studied. The effect of soil properties (soil pH, temperature and microbial biomass) on the degradation of fenamiphos was determined. The rate of degradation increased with increase in temperature.

Toxicity of chlorpyrifos and TCP alone and in combination to Daphnia carinata: the influence of microbial degradation in natural water.

The acute toxicity of chlorpyrifos and its principal metabolite 3,5,6-trichloropyridinol (TCP) alone and in combination to a cladoceran, Daphnia carinata, was studied in both cladoceran culture medium and natural water collected from a local suburban stream. TCP was found to be more toxic than its parent chemical chlorpyrifos to Daphnia survival in cladoceran culture medium. However, TCP in natural water was not toxic to D.

Toxicity of fenamiphos and its metabolites to the cladoceran Daphnia carinata: the influence of microbial degradation in natural waters.

The acute toxicity of an organophosphorous pesticide, fenamiphos and its metabolites, fenamiphos sulfoxide, fenamiphos sulfone, fenamiphos phenol, fenamiphos sulfoxide phenol and fenamiphos sulfone phenol, to a cladoceran, Daphnia carinata was studied in both cladoceran culture medium and natural water collected from a local river. The toxicity followed the order: fenamiphos>fenamiphos sulfone>fenamiphos sulfoxide. The hydrolysis products of fenamiphos, F.