Biotic and abiotic degradation of illicit drugs, their precursor, and by-products in soil

This study presents the first systematic information on the degradation patterns of clandestine drug laboratory chemicals in soil. The persistence of five compounds - parent drugs (methamphetamine, 3,4-methylenedioxymethamphetamine (MDMA)), precursor (pseudoephedrine), and synthetic by-products N-formylmethylamphetamine and 1-benzyl-3-methylnaphthalene) - were investigated in laboratory scale for 1 year in three different South Australian soils both under non-sterile and sterile conditions. The results of the degradation study indicated that 1-benzyl-3-methylnaphthalene and methamphetamine persist for a long time in soil compared to MDMA and pseudoephedrine; N-formylmethylamphetamine exhibits intermediate persistence. The role of biotic versus abiotic soil processes on the degradation of target compounds was also varied significantly for different soils as well as with the progress in incubation period. The degradation of methamphetamine and 1-benzyl-3-methylnaphthalene can be considered as predominantly biotic as no measureable changes in concentrations were recorded in the sterile soils within a 1 year period. The results of the present work will help forensic and environmental scientists to precisely determine the environmental impact of chemicals associated with clandestine drug manufacturing laboratories.     

Integrated analysis of the effects of agricultural management on nitrogen fluxes at landscape scale

The integrated modelling system INITIATOR was applied to a landscape in the northern part of the Netherlands to assess current nitrogen fluxes to air and water and the impact of various agricultural measures on these fluxes, using spatially explicit input data on animal numbers, land use, agricultural management, meteorology and soil. Average model results on NH₃ deposition and N concentrations in surface water appear to be comparable to observations, but the deviation can be large at local scale, despite the use of high resolution data. Evaluated measures include: air scrubbers reducing NH₃ emissions from poultry and pig housing systems, low protein feeding, reduced fertilizer amounts and low-emission stables for cattle. Low protein feeding and restrictive fertilizer application had the largest effect on both N inputs and N losses, resulting in N deposition reductions on Natura 2000 sites of 10% and 12%, respectively.     

Assessing seasonal and spatial trends of persistent organic pollutants (POPs) in Indian agricultural regions using PUF disk passive air samplers

The first survey of persistent organic pollutant (POP) concentrations in air across several Indian agricultural regions was conducted in 2006-2007. Passive samplers comprising polyurethane foam (PUF) disks were deployed on a quarterly basis at seven stations in agricultural regions, one urban site and one background site. The project was conducted as a sub-project of the Global Atmospheric Passive Sampling (GAPS) Network. In addition to revealing new information on air concentrations of several organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs), the study has demonstrated the feasibility of conducting regional-scale monitoring for POPs in India using PUF disk samplers. The following analytes were detected with relatively high concentrations in air (mean for 2006 and 2007, pg/m³): α- and γ-hexachlorocyclohexane (HCH) (292 and 812, respectively); endosulfan I and II (2770 and 902, respectively); p,p′-DDE and p,p′-DDT (247 and 931, respectively); and for the sum of 48 PCBs, 12,100 (including a site with extremely high air concentrations in 2007) and 972 (when excluding data for this site).     

Variability of dust iron solubility in atmospheric waters: Investigation of the role of oxalate organic complexation

Atmospheric dust deposition is a major external iron source for remote surface ocean waters. Organic complexation is known to play a role in the dissolution of iron-containing minerals. In this paper, we present our study on the effect of oxalate on dust iron solubility in simulated rainwater. Our results reveal that the solubility of iron carried by analogs of different African dusts varies with the dust source. Our experiments indicate a positive linear correlation between iron solubility and oxalate concentration. Soluble iron (SFe) increases from 0.0025(±0.0005)% to 0.26(±0.01)% of total iron, considering all dust sources and with oxalate concentrations ranging from 0 to 8 μM. These results show that the observed variability of iron solubility in aerosols collected over the Atlantic Ocean is, at least partly, due to an increase in dust iron solubility, with the presence of oxalate complexation, rather than to the presence of more soluble anthropogenic iron. Considering the mineralogical composition of those particles, experiments with pure minerals (hematite, goethite and illite) were performed to study the dissolution process. We found that oxalate promotes the solubility of iron contained in clay and hence confirmed that more than 95% of SFe from soil dust is provided by clay (illite). This experimental work enables us to establish a parameterization of iron solubility in dust as a function of oxalate concentration and based on the individual iron solubility of pure iron-bearing minerals usually present in dust particles. Finally, our results emphasize that oxalate contributes to iron solubility on the same order of magnitude as the acid processes. Organic complexation appears to be a process that increases iron solubility and likely enhances the bioavailability of iron from dust.     

An ecotoxicological approach for hazard identification of energy ash

Within the EU, ash should be classified by its inherent hazardous effects under criterion H-14 (ecotoxic) in the Directive on waste (2008/98/EC). Today, however, there are no harmonized quantitative criterions for such a classification, but it is stated that biological test systems can be used. In this study seven ash materials were leached and characterized, both biologically and chemically. The objectives were to evaluate if (a) clear concentration-response relationships could be achieved for the selected toxicity tests (bacteria, algae, crustacean and fish), (b) some test(s) are generally more sensitive and (c) the toxic responses were consistent with the chemical analyzes. Interestingly, our results indicate that high concentrations of non-hazardous components (Ca, K) influenced the toxicity of almost all ash eluates, whereas hazardous components (e.g. Zn, Pb) only influenced the toxicity of the eluates ranked as most hazardous. If considering both hazardous and non-hazardous substances, the observed toxic responses were relatively consistent with the chemical analyzes. Our results further showed that the (sub)chronic tests were much more sensitive than the acute tests. However, the use of extrapolation factors to compensate for using the less sensitive acute tests will likely lead to either over- or underestimations of toxicity. Our recommendation is therefore that classification of waste according to H-14 should be based on (sub)chronic test data. Finally, given that treatment of the eluates prior to toxicity testing has a major significance on the concentration and speciation of released substances, further studies are needed in order to propose a relevant testing scheme.     

Bioconversion of dairy manure by black soldier fly (Diptera: Stratiomyidae) for biodiesel and sugar production

Modern dairies cause the accumulation of considerable quantity of dairy manure which is a potential hazard to the environment. Dairy manure can also act as a principal larval resource for many insects such as the black soldier fly, Hermetia illucens. The black soldier fly larvae (BSFL) are considered as a new biotechnology to convert dairy manure into biodiesel and sugar. BSFL are a common colonizer of large variety of decomposing organic material in temperate and tropical areas. Adults do not need to be fed, except to take water, and acquired enough nutrition during larval development for reproduction. Dairy manure treated by BSFL is an economical way in animal facilities. Grease could be extracted from BSFL by petroleum ether, and then be treated with a two-step method to produce biodiesel. The digested dairy manure was hydrolyzed into sugar. In this study, approximately 1248.6 g fresh dairy manure was converted into 273.4 g dry residue by 1200 BSFL in 21 days. Approximately 15.8 g of biodiesel was gained from 70.8 g dry BSFL, and 96.2 g sugar was obtained from the digested dairy manure. The residual dry BSFL after grease extraction can be used as protein feedstuff.     

Environmental assessment of garden waste management in the Municipality of Aarhus, Denmark

An environmental assessment of six scenarios for handling of garden waste in the Municipality of Aarhus (Denmark) was performed from a life cycle perspective by means of the LCA-model EASEWASTE. In the first (baseline) scenario, the current garden waste management system based on windrow composting was assessed, while in the other five scenarios alternative solutions including incineration and home composting of fractions of the garden waste were evaluated. The environmental profile (normalised to Person Equivalent, PE) of the current garden waste management in Aarhus is in the order of −6 to 8 mPE Mg⁻¹ ww for the non-toxic categories and up to 100 mPE Mg⁻¹ ww for the toxic categories. The potential impacts on non-toxic categories are much smaller than what is found for other fractions of municipal solid waste. Incineration (up to 35% of the garden waste) and home composting (up to 18% of the garden waste) seem from an environmental point of view suitable for diverting waste away from the composting facility in order to increase its capacity. In particular the incineration of woody parts of the garden waste improved the environmental profile of the garden waste management significantly.     

Anthropogenic and naturally occurring polybrominated phenolic compounds in the blood of cetaceans stranded along Japanese coastal waters

We determined the residue levels and patterns of hydroxylated polybrominated diphenyl ethers (OH-PBDEs), and related compounds, such as PBDEs, methoxylated PBDEs (MeO-PBDEs), and bromophenols (BPhs) in the blood of eleven cetacean species stranded along the Japanese coasts. The dominant OH- and MeO-PBDE isomers found in all cetaceans were 6OH-BDE47 and 6MeO-BDE47. Additionally, 2,4,6-triBPh was dominant isomer in all cetaceans. In contrast, specific differences in the distribution of para- and meta- OH-PBDE isomers and some BPhs (potential PBDEs metabolites) were found among the cetaceans.Residue levels of ΣMeO-PBDEs and 6OH-BDE47 + 2′OH-BDE68, and 2,4,6-triBPh and 6OH-BDE47 + 2′OH-BDE68 showed a significant positive correlation. These results may suggest that the large percentages of OH-PBDEs, MeO-PBDEs and 2,4,6-triBPh might share common source (i.e. biosynthesis by marine organisms), or metabolic pathway in cetacean species. Significant correlations were found between the concentrations of BDE99 and 2,4,5-triBPh. This result suggested that 2,4,5-triBPh in cetaceans could be a metabolite of BDE99.     

Land application of tylosin and chlortetracycline swine manure: Impacts to soil nutrients and soil microbial community structure

The land application of aged chortetracycle (CTC) and tylosin-containing swine manure was investigated to determine associated impacts to soil microbial respiration, nutrient (phosphorus, ammonium, nitrate) cycling, and soil microbial community structure under laboratory conditions. Two silty clay loam soils common to southeastern South Dakota were used. Aerobic soil respiration results using batch reactors containing a soil-manure mixture showed that interactions between soil, native soil microbial populations, and antimicrobials influenced CO(2) generation. The aged tylosin treatment resulted in the greatest degree of CO(2) inhibition, while the aged CTC treatment was similar to the no-antimicrobial treatment. For soil columns in which manure was applied at a one-time agronomic loading rate, there was no significant difference in soil-P behavior between either aged CTC or tylosin and the no-antimicrobial treatment. For soil-nitrogen (ammonium and nitrate), the aged CTC treatment resulted in rapid ammonium accumulation at the deeper 40cm soil column depth, while nitrate production was minimal. The aged CTC treatment microbial community structure was different than the no-antimicrobial treatment, where amines/amide and carbohydrate chemical guilds utilization profile were low. The aged tylosin treatment also resulted in ammonium accumulation at 40 cm column depth, however nitrate accumulation also occurred concurrently at 10 cm. The microbial community structure for the aged tylosin was also significantly different than the no-antimicrobial treatment, with a higher degree of amines/amides and carbohydrate chemical guild utilization compared to the no-antimicrobial treatment. Study results suggest that land application of CTC and tylosin-containing manure appears to fundamentally change microbial-mediated nitrogen behavior within soil A horizons.     

Release kinetics of β-cyfluthrin from its encapsulated formulations in water

Controlled release formulations of β-cyfluthrin, a non-systemic, broad spectrum contact insecticide, have been prepared using laboratory synthesized poly(ethylene glycol) (PEG) based amphiphilic copolymers. Copolymers of polyethylene glycols of different molecular weights and various dimethyl esters, viz. dimethyl isophthalate, which self assemble into nano micellar aggregates in aqueous media, have been synthesized. The kinetics of β-cyfluthrin from developed controlled release (CR) formulations were studied in comparison with that of the commercially available 025 SC. Release from the commercial formulation was faster than with the developed CR formulations. The rate of release of encapsulated β-cyfluthrin from nano micellar aggregates is reduced by increasing the molecular weight of PEG. The diffusion exponent (n value) of β-cyfluthrin in water ranged from 0.427 to 0.622 in the tested formulations. The release was diffusion controlled with a half-release time (t(?)) of 3.92 to 7.9 days in water from different formulations, and the period of optimum availability (POA) of β-cyfluthrin ranged from 1.4 to 20.5 days. The results suggest that the application rate of β-cyfluthrin can be optimized to achieve insect control at the desired level and period.