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Pesticide misuse incidents are reported worldwide each year. The potential exposure to pesticides creates a concern for occupants in affected homes, apartments, and other occupied buildings. Pesticides that are improperly applied within these locations may require remediation prior to reoccupation. Incident response personnel rely heavily on data from sampling results to identify residue levels and determine when site remediation is complete. Surface wipe samples are often collected for this purpose. Therefore, it is important to ensure sampling and analysis procedures are well established for the contaminants of concern, particularly for wipe sampling variables that can affect analysis results. This investigation evaluated the effects of surface wipe media, wipe wetting solvents, pesticide concentrations effects, composite sampling, surface types, and pesticide formulation effects on analysis results for fipronil, permethrin, and deltamethrin. Tested surface types included galvanized steel, vinyl tile, and plywood. Wipe media included pre-packaged, sterile cotton gauze, pre-cleaned cotton twill, and a pre-packaged, pre-wetted wipes. Surface recovery results are reported for commercially available fipronil formulations and compared to technical grade fipronil solutions. Fipronil recoveries were 92–107 % for twill wipes, 81–98 % for cotton gauze wipes, and 79 % for pre-packaged, pre-wetted wipes on a galvanized steel surface. Permethrin recoveries were 83–116 % for twill wipes, 66–94 % for cotton gauze wipes, and 73 % for pre-packaged, pre-wetted wipes on a galvanized steel surface. Deltamethrin recoveries were 67–88 % for twill wipes, 55–71 % for cotton gauze wipes, and 63 % for pre-packaged, pre-wetted wipes on a galvanized steel surface. The data collected in this study can inform surface wipe sampling methods and potentially assist in obtaining more accurate sampling data associated with pesticide misuse incidents involving the target analytes.

This protocol provides an example of a laboratory process for conducting laundering studies that generate data on viral disinfection. While the protocol was developed for research during the coronavirus disease 2019 (COVID-19) pandemic, it is intended to be a framework, adaptable to other virus disinfection studies; it demonstrates the steps for preparing the test virus, inoculating the test material, assessing visual and integrity changes to the washed items due to the laundering process, and quantifying the reduction in viral load. Additionally, the protocol outlines the necessary quality control samples for ensuring the experiments are not biased by contamination and measurements/observations that should be recorded to track the material integrity of the personal protective equipment (PPE) items after multiple laundering cycles. The representative results presented with the protocol use the Phi6 bacteriophage inoculated onto cotton scrub, denim, and cotton face-covering materials and indicate that the hot water laundering and drying process achieved over a 3-log (99.9%) reduction in viral load for all samples (a 3-log reduction is the disinfectant performance metric in U.S. Environmental Protection Agency’s Product Performance Test Guideline 810.2200). The reduction in viral load was uniform across different locations on the PPE items. The results of this viral disinfection efficacy testing protocol should help the scientific community explore the effectiveness of home laundering for other types of test viruses and laundering procedures.

AIMS: (1) To develop an analytical method for recovery and quantification of bacteriophage MS2 – as a surrogate for foot and mouth disease virus (FMDV) – from complex porous surfaces, with and without the presence of laboratory-developed agricultural grime; (2) To evaluate, with a 4-log dynamic range, the virucidal activity of common biocides for their ability to decontaminate surfaces, and hence remediate facilities, following a foreign animal disease contamination incident. METHODS AND RESULTS: An analytical method was developed and optimized for MS2 recovery from simulated agricultural surfaces. The addition of Dey-Engley neutralizing broth to an extraction buffer improved MS2 viability in liquid extracts, with optimal analytical holding times determined as < 8h to ≤24h, depending on matrix. The recovery of MS2 from surface materials decreased in order: non-porous reference material > grimed porous materials > non-grimed porous materials. In disinfectant testing, two spray applications of pAB were effective against MS2 (≥ 4-log reduction) on all operational-scale materials. 2% citric acid had limited effectiveness, with ≥ 4-log reduction observed on a selected subset of grimed concrete samples. CONCLUSIONS: Decontamination efficacy test results can be affected by surface characteristics, extraction buffer composition, analytical holding time, and surface-specific organism survivability. Efficacy should be evaluated using a test method that reflects the environmental characteristics of the intended application. SIGNIFICANCE AND IMPACT OF THE STUDY: The results of this study demonstrate the importance of analytical method verification tests for disinfectant testing prior to application in complex environments.

Pesticide misuse incidents in residential indoor areas are typically associated with misapplications that are inconsistent with the label directions of the product. Surface wipe sampling and analysis procedures are relied upon to evaluate the extent of indoor contamination and the remediation efforts successfully. In general, surface wipe sampling procedures are widely varied, which can complicate the comparison of the results and data interpretation. Wipe sampling parameters were studied for the insecticides malathion and carbaryl. The parameters evaluated include wipe media, wetting solvents, composite sampling, surface concentration, and the influence of differing product formulations. Porous and nonporous surfaces tested include vinyl tile, plywood and painted drywall (porous/permeable) and stainless steel and glass (nonporous/impermeable). Specific wipe materials included pre-packaged sterile-cotton gauze, pre-cleaned cotton twill, cotton balls, and a pre-packaged, pre-wetted wipe. Commercially available insecticide formulations were tested, and the results were compared to surfaces fortified with neat analytes to determine surface recovery results (efficiency). A sampling procedure to measure pesticide residues was developed, and variables associated with the sampling methods were evaluated to clarify how estimations of surface residues are impacted. Malathion recoveries were 73-86% for twill and pre-wetted, pre-packaged isopropanol wipes on nonporous materials. Malathion formulations ranged from 78 to 124% for pre-wetted, pre-packaged isopropanol wipes and cotton gauze wipes on nonporous materials. Carbaryl and carbaryl formulation recoveries were 82-115% and 77-110%, respectively, on nonporous surfaces for all tested wipe materials. While not every wipe sampling variable could be tested, the collected information from this study may be useful and applied to sampling plans for classes of chemicals with similar physicochemical properties.

Environmental sampling is a critical component of the post decontamination verification process following a bioterrorism event. The current work was performed to produce a less labor-intensive method for processing cellulose sponge-wipes used for sampling areas potentially contaminated with low concentrations (i.e., post-decontamination) of Bacillus anthracis spores . An alternative fast-analysis processing method was compared to the processing protocol validated by the Centers for Disease Control and Prevention (CDC) for the Laboratory Response Network (LRN). Glazed tile coupons (1102 cm 2) were inoculated with 50, 500, or 5000 spores of Bacillus thuringiensis subsp. kurstaki (Btk), then sampled with cellulose sponges. Sampling was limited to a 25- by 25-cm area and performed in the same manner as the CDC sampling method. Samples were then processed using either the alternative “Fast Analysis” method or the “CDC method”. Three different analysts repeated the tests at each concentration utilizing each method. Mean recoveries, labor time, and potentially hazardous waste produced were compared for the two methods. The mean percent recoveries and standard errors for the samples processed using the “CDC method” were 39.9 ± 6.7, 43 ± 7.6, and 36.8 ± 10.1 for the 5000, 500, and 50 spore loading levels, respectively; compared to 54.2 ± 12.9, 64.2 ± 21.7, and 45.2 ± 8.6 for the “Fast Analysis” method. At each titer tested the “Fast Analysis” method resulted in a statistically significant higher percent recovery. Furthermore, analysts processed samples utilizing the “Fast Analysis” method in less than half the time and generated half as much potentially hazardous waste compared to the “CDC method”.

The goal of this study was to provide quantitative efficacy information relevant to technical and forensic decontamination that may assist safety officers in mitigating health hazards to personnel and minimizing the potential transfer of chemicals by cross-contamination from a chemical incident scene. To achieve this goal, decontamination solutions were evaluated using representative contact times of personal protective equipment (PPE) and related materials with the chemical contaminant at operationally relevant decontamination dwell times. The study included four toxic industrial chemicals (TICs) and two chemical warfare agent (CWA) surrogates, eight decontamination solutions and seven PPE-related materials that would transition through a personnel decontamination line. Measured neutralization efficacies following a 2.0-min dwell time varied strongly by chemical with no/very minimal efficacy observed for decontaminants against materials contaminated with nitrobenzene, chlordane, and phenol. Higher efficacies up to 60% were observed for full strength bleach, RSDL® and EasyDECON® DF200 products against malathion, carbaryl, and 2-chloroethyl ethyl sulfide. Other decontamination solutions like detergent and water, 10× diluted bleach, and pH-amended bleach were found to be non-efficacious (less than 20%) against any of the chemicals. The short dwell time and limited amount of decontaminant on the contaminated surface limits the expected efficacy. Therefore, the contribution of neutralization to the decontamination process while responders are preparing to doff personal protective equipment may be limited.

The improper and excessive use of pesticides in indoor environments can result in adverse human health effects, sometimes necessitating decontamination of residential or commercial buildings. A lack of information on effective approaches to remediate pesticide residues prompted the decontamination and persistence studies described in this study. Decontamination studies evaluated the effectiveness of liquid-based surface decontaminants against pesticides on indoor surfaces. Building materials were contaminated with 25–2,400 μg/100cm(2) of the pesticides malathion, carbaryl, fipronil, deltamethrin, and permethrin. Decontaminants included both off-the-shelf and specialized solutions representing various chemistries. Pesticides included in this study were found to be highly persistent in a dark indoor environment with surface concentrations virtually unchanged after 140 days. Indoor light conditions degraded some of the pesticides, but estimated half-lives exceeded the study period. Decontamination efficacy results indicated that the application of household bleach or a hydrogen peroxide-based decontaminant offered the highest efficacy, reducing malathion, fipronil, and deltamethrin by >94–99% on some surfaces. Bleach effectively degraded permethrin (>94%), but not carbaryl (71–99%) but not permethrin (

The efficacies of enzyme-based technologies developed for the decontamination of surfaces contaminated with chemical warfare agent simulants were measured as a function of operating and environmental conditions mimicking possible outdoor conditions. Bench-scale decontamination testing was used to evaluate two enzyme-containing products for their ability to neutralize paraoxon and 2-chloroethyl phenyl sulfide (2-CEPS) selected as simulants of G-, V-series chemical agents and sulfur mustard, respectively. Residual amounts of the simulant on galvanized metal coupons were measured following application of the enzyme. Both enzymatic decontamination methods performed fairly well against the simulants, with higher efficacies at higher temperature against paraoxon and the opposite trend for the second enzyme solution against 2-CEPS. A longer interaction period resulted in better efficacy. Reapplication of fresh enzyme solution yielded a major improvement in efficacy. The neutral pH of both enzyme solutions makes ...

The first comprehensive set of U.S. data on polybrominated diphenylether (PBDE) concentrations from municipal waste combustion (MWC), with more than 40 PBDE congeners reported, was compared to ambient air levels of PBDEs in the U.S. The PBDE profiles in the raw MWC flue gas reflected the historical production and usage pattern of PBDE-based flame retardants in North America, which favored Penta- and Deca- BDE formulations. The pattern of selected, routinely measured in the environment, PBDEs (TeBDE-47, PeBDE-99, PeBDE-100, HxBDE-153 and DcBDE-209) was similar in the MWC emissions and profiles most commonly reported for the U.S. atmosphere. The mean Σ PBDE concentrations in the clean flue gases collected from the stack were 0.13 and 1.7 ng dscm −1 during the steady state and transients of MWC, respectively (which was 98.6% reduction compare to the levels in the raw flue gases). The major PBDE congeners in the MWC flue gases were those typically found in PBDE technical mixes (TeBDE-47, PeBDE-99, PeBDE-100, HxBDE-153, HpBDE-183, OcBDE-197, NoBDE-206, NoBDE-207, NoBDE-208, DcBDE-209). The profile of the PBDEs in the raw flue gas was dominated by heavier congeners, especially DcBDE-209, while the profile of the stack flue gases profile was dominated by the lighter congeners (TeBDE-47, PeBDE-99, PeBDE-100 accounted for around 80% of total stack emissions). Some of the MWC flue gas samples exhibited enrichment of lower brominated congeners that are minor or not present in the technical mixtures, suggesting that debromination occurs during combustion. Congeners substituted in non- and mono- ortho positions (TeBDE-77, PeBDE-126, HxBDE-156 and -169) were detected mostly during the transients of MWC.

Concentrations of polybrominated dibenzo-p-dioxins, and -dibenzofurans (PBDDs/Fs) and polychlorinated dibenzo-p-dioxins, and -dibenzofurans (PCDDs/Fs), were determined in the pre- and post-air pollution control system (APCS) flue gas of a municipal waste combustor (MWC). Operational transients of the combustor were found to considerably increase levels of PBDDs/Fs and PCDDs/Fs compared to steady state operation, both for the raw and clean flue gas; ΣPBDDs/Fs increased from 72.7 to 700 pg dscm(-1) in the raw, pre-APCS gas and from 1.45 to 9.53 pg dscm(-1) in the post-APCS flue gas; ΣPCDDs/Fs increased from 240 to 960 ng dscm(-1) in the pre-APCS flue gas, and from 1.52 to 16.0 ng dscm(-1) in the post-APCS flue gas. The homologue profile of PBDDs/Fs and PCDDs/Fs in the raw flue gas (steady state and transients) was dominated by hexa- and octa-isomers, while the clean flue gas homologue profile was enriched with tetra- and penta-isomers. The efficiency of the APCS for PBDD/F and PCDD/F removal was estimated as 98.5% and 98.7%, respectively. The cumulative TEQ(PCDD/F+PBDD/F) from the stack was dominated by PCDD/F: the TEQ of PBDD/F contributed less than 0.1% to total cumulative toxic equivalency of MWC stack emissions.

Disposal of electronic waste (e-waste) in landfills, incinerators, or at rudimentary recycling sites can lead to the release of toxic chemicals into the environment and increased health risks. Developing e-waste recycling technologies at commercial facilities can reduce the release of toxic chemicals and efficiently recover valuable materials. While these e-waste operations represent a vast improvement over previous approaches, little is known about environmental releases, workplace exposures, and potential health impacts. In this study, airborne particulate matter (PM) was measured at various locations within a modern U.S.-based e-waste recycling facility that utilized mechanical processing. In addition, composite size fractionated PM (coarse, fine and ultrafine) samples were collected, extracted, chemically analyzed, and given by oropharyngeal aspiration to mice or cultured with lung slices for lung toxicity tests. Indoor total PM concentrations measured during the study ranged from 220 to 1200 μg/m(3). In general, the coarse PM (2.5-10 μm) was 3-4 times more abundant than fine/ultrafine PM (2.5 μm). The coarse PM contained higher levels of Ni, Pb, and Zn (up to 6.8 times) compared to the fine (0.1-2.5 μm) and ultrafine (0.1 μm) PM. Compared to coarse PM measurements from a regional near-roadway study, Pb and Ni were enriched 170 and 20 times, respectively, in the indoor PM, with other significant enrichments (10 times) observed for Zn and Sb, modest enrichments (5 times) for Cu and Sr, and minor enrichments (2 times) for Cr, Cd, Mn, Ca, Fe, and Ba. Negligible enrichment (2 times) or depletion (1 time) were observed for Al, Mg, Ti, Si, and V. The coarse PM fraction elicited significant pro-inflammatory responses in the mouse lung at 24 h postexposure compared to the fine and ultrafine PM, and similar toxicity outcomes were observed in the lung slice model. We conclude that exposure to coarse PM from the facility caused substantial inflammation in the mouse lung and enrichment of these metals compared to levels normally present in the ambient PM could be of potential health concern.

Open burning for waste disposal is, in many countries, the dominant source of polychlorinated dibenzodioxins, dibenzofurans and biphenyls (PCDD/PCDF/PCB) release to the environment. To generate emission factors for open burning, experimental pile burns of about 100 kg of household waste were conducted with emissions sampling. From these experiments and others conducted by the same authors it is found that less compaction of waste or active mixing during the fire--"stirring"--promotes better combustion (as evidenced by lower CO/CO(2) ratio) and reduces emissions of PCDD/PCDF/PCB; an intuitive but previously undemonstrated result. These experiments also support previous results suggesting PCDD/PCDF/PCB generation in open burning - while still highly variable - tends to be greater in the later (smoldering) phases of burning when the CO/CO(2) ratio increases.