Provision of forensic healthcare services for police custodial settings in England, Wales and Northern Ireland: Current practice and implications for other services?

Provision of forensic healthcare services may affect patient safety and criminal justice outcomes. We reviewed models of delivery for services in police custody in terms of cost, types of healthcare professionals and their minimum required experience, training and qualification. Relevant information was requested under the Freedom of Information Act from all police services in England, Wales and Northern Ireland. Additional information was sought from the London Ambulance Service and the Metropolitan Police Service. A third of respondent police services refused to provide the requested information and only a small minority answered the questions in their entirety. Many police services cited excessive cost and commercial interests as reasons for not providing the information. A marked variation in models of forensic healthcare provision across police services which responded was identified. London Ambulance Service call-outs to Metropolitan Police Service custody suites for those arrested varied from 0% to 3.8%. There is substantial inconsistency and variability of information on forensic healthcare services in police custody. A standardised national dataset of all aspects of police custodial healthcare (irrespective of by whom such services are provided) should be established. We advise that the Association of Police & Crime Commissioners, College of Policing the National Police Chiefs' Council and NHS England Health and Justice engage on these matters and work with the Faculty of Forensic & Legal Medicine, the United Kingdom Association of Forensic Nurses and Paramedics, and the College of Paramedics to restart the transfer of all police custodial healthcare services to the National Health Service.

Complaints against health care professionals providing police custodial and forensic medical/health care services in England, Wales and Northern Ireland - what do we know?

Awareness of the nature and frequency of complaints against health care professionals working in police custodial health care services could provide opportunities to improve patient safety. To explore this freedom of information requests were sent to police services in England, Wales and Northern Ireland, to professional regulatory bodies and to the Independent Office for Police Conduct. Eighty-seven percent of police services responded but only a minority provided complete responses, with data not being held, or not being held in an easily retrievable format, being provided as reasons. The nature and frequency of complaints were similar to a previous 2017 study, suggesting a failure to learn lessons from the investigation of complaints and implement change in clinical practice. No evidence of an accessible complaints handling and recording procedure was provided across the police services surveyed. Regulatory bodies provided some information on the nature of complaints made against doctors and nurses working in police custodial settings, but that for paramedics was unable to do so. It is recommended that the communication loop between police services, those bodies providing health care and forensic medical services and regulatory bodies needs to be closed. A common reporting system or the application of established complaints handling procedures and reporting structures, which could be achieved by transferring these services to the National Health Service, may enhance patient safety in police custody.

Diversity of Carbonyl Compounds in Biogas and Natural Gas Revealed Using High-Resolution Mass Spectrometry and Nontarget Analysis.

Airborne carbonyl compounds such as formaldehyde, acrolein, and methyl ethyl ketone have long been chemicals-of-concern in the environment due to their reactivity and their potential for negative health effects. Standard methods for determining carbonyls in air, which focus on a set of 15 or fewer compounds, involve derivatization to form nonvolatile hydrazones, which can readily be analyzed via liquid chromatography (LC) with ultraviolet detectors. Here, we apply a new LC-high-resolution mass spectrometry (HRMS) method to natural gas and a variety of upgraded biofuels to better assess their total carbonyl profile using the inherent selectivity of the standard sampling methodology and the selectivity and sensitivity of HRMS. The standard method accounted for only 64% of the total carbonyl content in natural gas and between 26 and 45% of the total carbonyl content in biogas sources, with the balance detected by the new LC/HRMS method. An additional 540 compounds with molecular formulas consistent with carbonyl compounds were detected compared to only 14 target compounds using the standard method. These results demonstrate that the established method dramatically under-reports both the total carbonyl load and the diversity of carbonyl species in natural gas and biogas samples.

Chemical and Toxicological Properties of Emissions from a Light-Duty Compressed Natural Gas Vehicle Fueled with Renewable Natural Gas.

Biogas consisting primarily of methane (CH4) and carbon dioxide (CO2) can be upgraded to a transportation fuel referred to as renewable natural gas (RNG) by removing CO2 and other impurities. RNG has energy content comparable to fossil compressed natural gas (CNG) but with lower life-cycle greenhouse gas (GHG) emissions. In this study, a light-duty cargo van was tested with CNG and two RNG blends on a chassis dynamometer in order to compare the toxicity of the resulting exhaust. Tests for reactive oxygen species (ROS), biomarker expressions (CYP1A1, IL8, COX-2), and mutagenicity (Ames) show that RNG exhaust has toxicity that is comparable or lower than CNG exhaust. Statistical analysis reveals associations between toxicity and tailpipe emissions of benzene, dibenzofuran, and dihydroperoxide dimethyl hexane (the last identification is considered tentative/uncertain). Further gas-phase toxicity may be associated with tailpipe emissions of formaldehyde, dimethyl sulfide, propene, and methyl ketene. CNG exhaust contained higher concentrations of these potentially toxic chemical constituents than RNG exhaust in all of the current tests. Photochemical aging of the vehicle exhaust did not alter these trends. These preliminary results suggest that RNG adoption may be a useful strategy to reduce the carbon intensity of transportation fuels without increasing the toxicity of the vehicle exhaust.

Statistical analysis of trace contaminants measured in biogas.

Biogas is a renewable energy fuel that can be treated to increase purity so that the resulting "biomethane" can be injected into the natural gas pipeline grid. The trace contaminants in biogas and biomethane make up a small fraction of the total gas but they still have the potential to cause adverse health effects and pipeline corrosion. This study investigates the statistical distributions of 17 trace metals, six mercaptans, hydrogen sulfide, ammonia, and six additional trace organic compounds. Twelve of these 31 trace contaminants have been previously identified as constituents of concern based on their toxicity profiles and through health risk assessment studies. Untreated and treated samples of biogas were collected from 12 different biogas production facilities using diverse feedstocks throughout California. Results show that most biogas trace contaminants follow a single log-normal distribution or a bi-modal lognormal distribution depending on the type of production facility. Treatment of biogas demonstrates some removal for all trace contaminants, but four constituents of concern (copper, lead, hydrogen sulfide, and methyl mercaptan) are predicted to have a >1% probability of exceeding trigger levels even after common treatments. This finding suggests that enhanced monitoring may be warranted for these contaminants. Several trace metals and volatile organic compounds (VOCs) were found to have seasonal trends with greater concentrations in the summer and lower concentrations in the winter suggesting that seasonal variation should be considered in future monitoring plans.

Surface modification induced cuprous oxide nanoparticle toxicity to duckweed at sub-toxic metal concentrations.

Nanoparticle capping agents are critical for controlling the growth, oxidation state, and final particle size during aqueous synthesis. However, despite the known phytotoxicity of cetyltrimethylammonium bromide (CTAB) to plants, it is used to synthesize metal oxide nanoparticles of uniform size and with mesoporous structure. Among the few studies that have investigated how CTAB influences nanoparticle toxicity, CTAB has never been identified as the primary cause of nanoparticle toxicity in environmental systems; rather nanoparticle surface charge or morphology was identified as the driver of toxicity in environmentally relevant systems. In the current study, CTAB release from CTAB surface modified Cu2O nanoparticles (SM-Cu2O NPs) inhibited duckweed (Landoltia punctata) growth, even when administered at subtoxic Cu concentrations. Organic ligands, such as humic acid (HA) and ethylenediaminetetraacetic acid (EDTA), lessened growth inhibition associated with exposure to SM-Cu2O NPs, likely through electrostatic and hydrophobic interactions with CTAB. Such results highlight the need for a more holistic approach to nanoparticle surface modification and improved communication between toxicologists and synthetic chemists to develop green alternatives for nanoparticle synthesis.

Composition and Toxicity of Biogas Produced from Different Feedstocks in California.

Biogas is a renewable energy source composed of methane, carbon dioxide, and other trace compounds produced from anaerobic digestion of organic matter. A variety of feedstocks can be combined with different digestion techniques that each yields biogas with different trace compositions. California is expanding biogas production systems to help meet greenhouse gas reduction goals. Here, we report the composition of six California biogas streams from three different feedstocks (dairy manure, food waste, and municipal solid waste). The chemical and biological composition of raw biogas is reported, and the toxicity of combusted biogas is tested under fresh and photochemically aged conditions. Results show that municipal waste biogas contained elevated levels of chemicals associated with volatile chemical products such as aromatic hydrocarbons, siloxanes, and certain halogenated hydrocarbons. Food waste biogas contained elevated levels of sulfur-containing compounds including hydrogen sulfide, mercaptans, and sulfur dioxide. Biogas produced from dairy manure generally had lower concentrations of trace chemicals, but the combustion products had slightly higher toxicity response compared to the other feedstocks. Atmospheric aging performed in a photochemical smog chamber did not strongly change the toxicity (oxidative capacity or mutagenicity) of biogas combustion exhaust.

Ultrafine Particle Emissions from Natural Gas, Biogas, and Biomethane Combustion.

Biogas and biomethane (=purified biogas) are major renewable fuels that play a pivotal role in the evolving global energy economy. Here, we measure ultrafine particle (UFP; Dp (particle diameter) < 100 nm) emissions from the combustion of biomethane and biogas produced from five different representative sources: two food waste digesters, two dairy waste digesters, and one landfill. Combustion exhaust for each of these sources is measured from one or more representative sectors including electricity generation, motor vehicles, and household use. Results show that UFP emissions are similar when using biomethane and natural gas with similar sulfur and siloxane content. Approximately 70% of UFPs emitted from water heaters and cooking stoves were semivolatile, but 30% of the UFPs were nonvolatile and did not evaporate even under extremely high dilution conditions. Photochemical aging of biomethane combustion exhaust and natural gas combustion exhaust produced similar amounts of secondary organic aerosol (SOA) formation. The results of the current study suggest that widespread adoption of biogas and biomethane as a substitute for natural gas will not significantly increase ambient concentrations of primary and secondary UFPs if advanced combustion technology is used and the sulfur and siloxane content is similar for biogas/biomethane and natural gas.

Dissolved organic matter reduces CuO nanoparticle toxicity to duckweed in simulated natural systems.

With increasing demand for recycled wastewater for irrigation purposes, there is a need to evaluate the potential for manufactured nanomaterials in waste water to impact crop production and agroecosystems. Copper oxide nanoparticles (CuO NPs) have previously been shown to negatively impact the growth of duckweed (Landoltia punctata) a model aquatic plant consumed by water fowl and widely found in agricultural runoff ditches in temperate climates. However, prior studies involving CuO NP toxicity to duckweed have focused on systems without the presence of dissolved organic matter (DOM). In the current study, duckweed growth inhibition was shown to be a function of aqueous Cu2+ concentration. Growth inhibition was greatest from aqueous CuCl2 and, for particles, increased with decreasing CuO particle size. The dissolution of CuO NPs in ½ Hoagland's solution was measured to increase with decreasing particle size and in the presence of Suwannee river humic and fulvic acids (HA; FA). However, the current results suggest that HA, and to a lesser extent, FA, decrease the toxicity of both CuO NPs and free ionized Cu to duckweed, likely by inhibiting Cu availability through Cu-DOM complex formation. Such results are consistent with changes to Cu speciation as predicted by speciation modeling software and suggest that DOM changes Cu speciation and therefore toxicity in natural systems.

Complaints against health-care professionals providing police custodial and forensic medical/health-care services and sexual offence examiner services in England, Wales and Northern Ireland.

Complaints management is an integral component of good clinical governance and an essential contributor to patient safety. Little is known about complaints against health-care professionals (HCPs) in police custodial settings and sexual assault referral centres. This study explored the frequency with which complaints are made against such HCPs working in England, Wales and Northern Ireland. It explored the nature of those complaints and the procedures by which they are investigated. Relevant information was requested from all police services in England, Wales and Northern Ireland; professional regulatory bodies; and the Independent Police Complaints Commission under the Freedom of Information Act (FOIA). Eighty-nine per cent of police services responded to the FOIA request. However, only a minority of these provided detailed information. Many police services cited the provision of health-care services by external providers as the reason for not holding information upon complaints. There was no evidence of any upward trend in the numbers of complaints over the study period. Delayed response to a request for attendance, incivility, medication issues and issues regarding the quality of reports and evidence were amongst the most common types of complaints described. A small number of responders provided copies of the disciplinary procedures used to manage complaints against HCPs. Significant heterogeneity exists in respect of complaints handling procedures across custodial and forensic medical/health-care services and sexual offence examiner services. An opportunity to identify learning for improvement is being missed as a result of the absence of standardised complaints handling procedures.

Direct green waste land application: How to reduce its impacts on greenhouse gas and volatile organic compound emissions?

Direct land application as an alternative to green waste (GW) disposal in landfills or composting requires an understanding of its impacts on greenhouse gas (GHG) and volatile organic compound (VOC) emissions. We investigated the effects of two approaches of GW direct land application, surface application and soil incorporation, on carbon dioxide (CO2), nitrous oxide (N2O) and methane (CH4), and VOC emissions for a 12month period. Five treatments were applied in fall 2013 on fallow land under a Mediterranean climate in California: 30cm height GW on surface; 15cm height GW on surface; 15cm height GW tilled into soil; control+till; control+no till. In addition, a laboratory experiment was conducted to develop a mechanistic understanding of the influence of GW application on soil O2 consumption and GHG emission. The annual cumulative N2O, CO2 and VOC emissions ranged from 1.6 to 5.5kgN2O-Nha(-1), 5.3 to 40.6MgCO2-Cha(-1) and 0.6 to 9.9kgVOCha(-1), respectively, and were greatly reduced by GW soil incorporation compared to surface application. Application of GW quickly consumed soil O2 within one day in the lab incubation. These results indicate that to reduce GHG and VOC emissions of GW direct land application, GW incorporation into soil is recommended.

Prenatal mercury exposure, autism, and developmental delay, using pharmacokinetic combination of newborn blood concentrations and questionnaire data: a case control study.

BACKGROUND: Methylmercury (MeHg), known for well over a century as a neurotoxin in adults, has more recently been studied for potential detrimental effects during early brain development. While several studies have estimated mercury exposure, they usually rely on either a single biomarker or questionnaire data, each of which has limitations. The goal of this paper was to develop a toxicokinetic model that incorporates both biomarker and questionnaire data to estimate the cumulative exposure to MeHg through seafood consumption using data collected from the Childhood Autism Risks from Genetics and the Environment (CHARGE) study. METHODS: We utilized a previously described discrete-time model that estimates blood MeHg concentration given a piecewise-constant ingestion rate and single-compartment pharmacokinetics. We measured newborn bloodspot Hg concentrations and obtained information pertaining to maternal fish consumption using a questionnaire. Using MeHg concentration estimates from the toxicokinetic model, cumulative MeHg exposure was estimated in children with autism, children with developmental delay, and typically developing children. Median estimated cumulative MeHg was compared among diagnostic groups using the Kruskal-Wallis Test. Multinomial logistic regression models were constructed to assess the association between cumulative MeHg concentration and the risk of autism and developmental delay (vs. typical development). RESULTS: The estimated average MeHg concentration of for all fish species consumed by mothers was 42 ppb. Median cumulative MeHg over gestation was similar across diagnostic groups (p-values raged from 0.91 to 0.98). After adjusting for potential confounding, we found no association between cumulative MeHg exposure and the risk of autism (OR = 0.95, 95% CI: 0.95, 1.12) or developmental delay (OR = 1.00, 95% CI: 0.89, 1.13). CONCLUSIONS: The toxicokinetic model described in this paper yielded fish MeHg concentration estimates that are consistent with fish species containing lower levels of MeHg. Overall, cumulative MeHg exposure does not appear to detectably elevate the risk of autism or developmental delay. Based on the regression standard error for the association between ASD and TD, we would have reported statistical significance for an adjusted odds ratio of 1.09 or larger. This method can easily be extended to other epidemiologic studies in which there is a biomarker measurement and questionnaire data regarding exposure.

A multicopper oxidase-related protein is essential for insect viability, longevity and ovary development.

Typical multicopper oxidases (MCOs) have ten conserved histidines and one conserved cysteine that coordinate four copper atoms. These copper ions are required for oxidase activity. During our studies of insect MCOs, we discovered a gene that we named multicopper oxidase-related protein (MCORP). MCORPs share sequence similarity with MCOs, but lack many of the copper-coordinating residues. We identified MCORP orthologs in many insect species, but not in other invertebrates or vertebrates. We predicted that MCORPs would lack oxidase activity due to the absence of copper-coordinating residues. To test this prediction, we purified recombinant Tribolium castaneum (red flour beetle) MCORP and analyzed its enzymatic activity using a variety of substrates. As expected, no oxidase activity was detected. To study MCORP function in vivo, we analyzed expression profiles of TcMCORP and Anopheles gambiae (African malaria mosquito) MCORP, and assessed RNAi-mediated knockdown phenotypes. We found that both MCORPs are constitutively expressed at a low level in all of the tissues we analyzed. Injection of TcMCORP dsRNA into larvae resulted in 100% mortality prior to adult eclosion, with death occurring mainly during the pharate pupal stage or late pharate adult stage. Injection of TcMCORP dsRNA into pharate pupae resulted in the death of approximately 20% of the treated insects during the pupal to adult transition and a greatly shortened life span for the remaining insects. In addition, knockdown of TcMCORP in females prevented oocyte maturation and, thus, greatly decreased the number of eggs laid. These results indicate that TcMCORP is an essential gene and that its function is required for reproduction. An understanding of the role MCORP plays in insect physiology may help to develop new strategies for controlling insect pests.

Prenatal and neonatal peripheral blood mercury levels and autism spectrum disorders.

BACKGROUND: Prenatal and early-life exposures to mercury have been hypothesized to be associated with increased risk of autism spectrum disorders (ASDs). OBJECTIVES: This study investigated the association between ASDs and levels of total mercury measured in maternal serum from mid-pregnancy and infant blood shortly after birth. METHODS: The study sample was drawn from the Early Markers for Autism (EMA) Study. Three groups of children who were born in Orange County, CA in 2000-2001 were identified: children with ASD (n=84), children with intellectual disability or developmental delay (DD) (n=49), and general population controls (GP) (n=159). Maternal serum specimens and newborn bloodspots were retrieved from the California Department of Public Health prenatal and newborn screening specimen archives. Blood mercury levels were measured in maternal serum samples using mass spectrometer and in infant bloodspots with a 213 nm laser. RESULTS: Maternal serum and infant blood mercury levels were significantly correlated among all study groups (all correlations >0.38, p<0.01). Adjusted logistic regression models showed no significant associations between ASD and log transformed mercury levels in maternal serum samples (ASD vs. GP: OR [95% CI]=0.96 [0.49-1.90]; ASD vs. DD: OR [95% CI]=2.56 [0.89-7.39]). Results for mercury levels in newborn blood samples were similar (ASD vs. GP: OR [95% CI]=1.18 [0.71-1.95]; ASD vs. DD: OR [95% CI]=1.96 [0.75-5.14]). CONCLUSIONS: Results indicate that levels of total mercury in serum collected from mothers during mid-pregnancy and from newborn bloodspots were not significantly associated with risk of ASD, though additional studies with greater sample size and covariate measurement are needed.

Sediment quality assessment in tidal salt marshes in northern California, USA: an evaluation of multiple lines of evidence approach.

The objective of this study was to evaluate the efficacy of integrating a traditional sediment quality triad approach with selected sublethal chronic indicators in resident species in assessing sediment quality in four salt marshes in northern California, USA. These included the highly contaminated (Stege Marsh) and relatively clean (China Camp) marshes in San Francisco Bay and two reference marshes in Tomales Bay. Toxicity potential of contaminants and benthic macroinvertebrate survey showed significant differences between contaminated and reference marshes. Sublethal responses (e.g., apoptotic DNA fragmentation, lipid accumulation, and glycogen depletion) in livers of longjaw mudsucker (Gillichthys mirabilis) and embryo abnormality in lined shore crab (Pachygrapsus crassipes) also clearly distinguished contaminated and reference marshes, while other responses (e.g., cytochrome P450, metallothionein) did not. This study demonstrates that additional chronic sublethal responses in resident species under field exposure conditions can be readily combined with sediment quality triads for an expanded multiple lines of evidence approach. This confirmatory step may be warranted in environments like salt marshes in which natural variables may affect interpretation of toxicity test data. Qualitative and quantitative integration of the portfolio of responses in resident species and traditional approach can support a more comprehensive and informative sediment quality assessment in salt marshes and possibly other habitat types as well.

Individual and combined effects of water quality and empty bed contact time on As(V) removal by a fixed-bed iron oxide adsorber: implication for silicate precoating.

The individual and combined effects of changes in water quality (i.e. pH, initial concentrations of arsenate (As(V)) and competing ions) and empty bed contact time (EBCT) on As(V) removal performance of a fixed-bed adsorber (FBA) packed with a nanostructured goethite-based granular porous adsorbent were systematically studied under environmentally relevant conditions. Rapid small scale column tests (RSSCTs) were extensively conducted at different EBCTs with synthetic waters in which pH and the concentrations of competing ions (phosphate, silicate, and vanadate) were controlled. In the absence of the competing ions, the effects of initial As(V) concentration, pH, and EBCT on As(V) breakthrough curves were successfully predicted by the homogeneous surface diffusion model (HSDM) with adsorption isotherms predicted by the extended triple layer model (ETLM). The interference effects of silicate and phosphate on As(V) removal were strongly influenced by pH, their concentrations, and EBCT. In the presence of silicate (≤21 mg/L as Si), a longer EBCT surprisingly resulted in worse As(V) removal performance. We suggest this is because silicate, which normally exists at much higher concentration and moves more quickly through the bed than As(V), occupies or blocks adsorption sites on the media and interferes with later As(V) adsorption. Here, an alternative operating scheme of a FBA for As(V) removal is proposed to mitigate the silicate preloading. Silicate showed a strong competing effect to As(V) under the tested conditions. However, as the phosphate concentration increased, its interference effect dominated that of silicate. High phosphate concentration (>100 µg/L as P), as experienced in some regions, resulted in immediate As(V) breakthrough. In contrast to the observation in the presence of silicate, longer EBCT resulted in improved As(V) removal performance in the presence of phosphate. Vanadate was found to compete with As(V) as strongly as phosphate. This study reveals the competitive interactions of As(V) with the competing ions in actual adsorptive treatment systems and the dependence of optimal operation scheme and EBCT on water quality in seeking improved As(V) removal in a FBA.

Mixed-culture polyhydroxyalkanoate production from olive oil mill pomace.

Polyhydroxyalkanoate (PHA) was produced in bench-scale sequencing batch reactors (SBRs) fed olive pomace fermentate containing a mixed microbial consortium. Initial anaerobic fermentation in a sequencing batch fermentor (SBF) produced soluble carbon compounds, mainly organic acids. SBF effluent was centrifuged, removing solids, and fed into a SBR where intracellular PHA was produced. Buffer pre-treatment of diluted olive pomace increased organic acid production 75% in SBF fermentate over no pre-treatment. Hydraulic retention time (HRT), solids retention time (SRT), pomace concentration/dilution, and aerobic operation vs. anoxic/oxic cycling were studied to improve PHA formation. Maximum %PHA achieved was 39% (on a dry-weight cell basis), and the highest volumetric productivity was 0.042 g PHA/L-day under fully aerobic conditions. The highest PHA conversion yield was 0.3625 g PHA/L fermentate.

Mobile source and livestock feed contributions to regional ozone formation in Central California.

A three-dimensional air quality model with 8 km horizontal resolution was applied to estimate the summertime ozone (O(3)) production from mobile sources and fermented livestock feed in California's San Joaquin Valley (SJV) during years 2000, 2005, 2010, 2015, and 2020. Previous studies have estimated that animal feed emissions of volatile organic compounds (VOCs) have greater O(3) formation potential than mobile-source VOC emissions when averaging across the entire SJV. The higher spatial resolution in the current study shows that the proximity of oxides of nitrogen (NO(x)) and VOC emissions from mobile sources enhances their O(3) formation potential. Livestock feed VOC emissions contributed 3-4 ppb of peak O(3) (8-h average) in Tulare County and 1-2 ppb throughout the remainder of the SJV during the CCOS 2000 July-August episode. In total, livestock feed contributed ~3.5 tons of the ground level peak O(3) (8 h average) in the SJV region, and mobile VOC contributed ~12 tons in this episode. O(3) production from mobile sources is declining over time in response to emissions control plans that call for cleaner fuels and engines with advanced emissions controls. Projecting forward to the year 2020, mobile-source VOC emissions are predicted to produce ~3 tons of the ground level peak O(3)(8-h average) and livestock feed VOC emissions are predicted to contribute ~2.5 tons making these sources nearly equivalent.

Determination of volatile organic compound emissions and ozone formation from spraying solvent-based pesticides.

Large-scale agricultural activities have come under scrutiny for possible contributions to the emission of ozone precursors. The San Joaquin Valley (SJV) of California is an area with intense agricultural activity that exceeds the federal ozone standards for more than 30 to 40 d yr(-1) and the more stringent state standards for more than 100 d yr(-1). Pesticides are used widely in both agricultural and residential subregions of the SJV, but the largest use, by weight of "active ingredient," is in agriculture. The objective of the study was to determine the role of pesticide application on airborne volatile organic compounds (VOC) concentrations and ozone formation in the SJV. The ozone formation from the pesticide formulation sprayed on commercial orchards was studied using two transportable smog chambers at four application sites during the summers of 2007 and 2008. In addition to the direct measurements of ozone formation, airborne VOC concentrations were measured before and after pesticide spraying using canister and sorbent tube sampling techniques. Soil VOC concentrations were also measured to understand the distribution of VOCs between different environmental compartments. Numerous VOCs were detected in the air and soil samples throughout the experiment but higher molecular weight aromatic hydrocarbons were the primary compounds observed in elevated concentrations immediately after pesticide spraying. Measurements indicate that the ozone concentration formed by VOC downwind of the orchard may increase up to 15 ppb after pesticide application, with a return back to prespray levels after 1 to 2 d.

Identification and quantitation of volatile organic compounds emitted from dairy silages and other feedstuffs.

High ground-level ozone continues to be an important human, animal, and plant health impediment in the United States and especially in California's San Joaquin Valley (SJV). According to California state and regional air quality agencies, dairies are one of the major sources of volatile organic compounds (VOCs) in the SJV. A number of recently conducted studies reported emissions data from different dairy sources. However, limited data are currently available for silage and otherfeed storages on dairies, which could potentially contribute to ozone formation. Because the impact of different VOCs on ozone formation varies significantly from one molecular species to another, detailed characterization of VOC emissions is essential to include all the important contributors to atmospheric chemistry and especially atmospheric reactivity. The present research study identifies and quantifies the VOCs emitted from various silages and other feedstuffs. Experiments were conducted in an environmental chamber under controlled conditions. Almost 80 VOCs were identified and quantified from corn (Zea mays L.), alfalfa (Medicago sativa L.),and cereal (wheat [Triticum aestivum L.] and oat [Avena sativava L.] grains) silages, total mixed ration (TMR), almond (Amygdalus communis L.) shells and hulls using gas chromatography-mass spectrometry and high performance liquid chromatography. The results revealed high concentrations of emitted alcohols and other oxygenated species. Lower concentrations of highly reactive alkenes and aldehydes were also detected. Additional quantitation and monitoring of these emissions are essential for assessment of and response to the specific needs of the regional air quality in the SJV.