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Passive air sampling (PAS) was used to evaluate organochlorine pesticides, polychlorinated biphenyls, polybrominated diphenyl ethers, polybrominated biphenyl, hexabromocyclododecane, polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans, and perfluoroalkane substances in the atmosphere of Medellin, Colombia. PAS was carried out for three months (four quarters per year) over two consecutive years (2017 and 2018). This study allowed establishing the baseline of some pollutants in the city against which future temporal trends can be assessed. Furthermore, monitoring results suggested releases of DDT in the city or surrounding areas despite this pollutant was banned many years ago in the country. Moreover, this study evidenced the limited scope of the national laboratories to analyze persistent organic pollutants, specially brominated and fluorinated contaminants. However, there is an installed capacity to analyze organochlorine pesticide and indicator PCB in future national monitoring plans. Therefore, it is essential to realize efforts to improve the analytical capacity and increase the scope of the national laboratories. Furthermore, the PAS strategy was valuable for monitoring these pollutants in air. Finally, the results provide an overall view of persistent organic pollutants levels and represent an initial attempt to monitor and surveillance the releases of these pollutants in the city.

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Organophosphate esters (OPEs) were comprehensively investigated in the air samples collected using high-volume samplers near the Chinese Great Wall Station in the Western Antarctic Peninsula over the period of 2014-2018. The concentrations of ∑8OPEs (gaseous + particle phases) ranged from 33.9 to 404 pg/m3 with a geometric mean of 119 ± 12.0 pg/m3. Tris [(2R)-1-chloro-2-propyl] phosphate (TCIPP) and tris(2-chloroethyl) phosphate (TCEP) dominated in the gaseous phase, while tris-n-butyl phosphate (TnBP) was the most abundant OPEs in the particle phase, followed by TCIPP and TCEP. An apparently temporal trend was observed for atmospheric ∑8OPEs over the five years, with a doubling time of about 3.8 years, which indicated continuous inputs of OPEs into the sampling area. The particle-bound ∑8OPEs accounted for 45% of the total, generally lower than that reported in the Arctic. Gas-particle partitioning modeling suggested that the partitioning of OPEs with higher logKOA values approached the steady state in the Antarctic air. The back-trajectory modeling showed that high levels of OPEs were usually associated with air inputs from the northwest of the peninsula. This suggested that long-range transport from South America, which was confirmed by the no temperature dependencies of OPEs concentrations (excluding TnBP). Nevertheless, a steady high level of particle-bound TnBP implied local sources in the Western Antarctic Peninsula, which required further investigation in future works.

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In the last decades, research regarding the dynamics of pesticides has grown, even in remote regions. Due to long-range atmospheric transport, environmental persistence and toxicological potential of organochlorine pesticides (OCPs), similar characteristics of current-use pesticides (CUPs) and their massive use in Brazil, these contaminants have become a major concern for environmental and human life. Thus, this study aimed to evaluate subgroups or individual chemicals of OCPs and CUPs, which could have travelled over two Conservation Unit sites in the Rio de Janeiro state. The study was carried out for 24 months, (2013-2015), in Itatiaia National Park (INP) and in the Serra dos Órgãos National Park (SONP), at ∼2400 and ∼2200 meters above sea level, respectively. The study was based on atmospheric passive sampling (polyurethane foam disks). Target pesticides were detected by means of gas chromatography device coupled with mass spectrometry (GC-MS). Significantly higher concentrations were measured in SONP when compared to INP. However, in broad terms, the contamination profile was quite similar for both national parks: The highest concentrations of endosulfan (INP - 1275 pg m-3 and SONP - 3202 pg m-3) were followed by cypermethrin (INP - 148 pg m-3 and SONP - 881 pg m-3) and chlorpyrifos (INP - 67 pg m-3 and SONP - 270 pg m-3). In agreement with previous studies, the atmospheric concentrations of legacy OCPs showed background air levels. The decrease of endosulfan over the years was highlighted with a parallel increase of chlorpyrifos, suggesting a collateral effect of the national bias of permissive and massive use of agrochemicals. CUPs seemed to behave like pseudo-persistent pollutants (pseudo-POPs). This is the first report of atmospheric concentrations of pyrethroids in Brazilian mountain regions, and possibly the first to investigate them in the air in South America or in any mountain region in the world.

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A calibration chamber has been designed and employed for the simple and easy determination of uptake sampling rate (RS) of volatile organic compounds (VOCs) from air using passive samplers. A flow of clean air was continuously spiked, at a constant VOC concentration, by the microinjection of a standard solution by means of a T-type tube. The developed system allowed the complete evaporation at room temperature of the standard solution in acetone and the air concentration of VOCs was easily controlled by the regulation of the clean air flow, the standard solution concentration and its flow. Active sampling was employed for monitoring the true concentration of the evaluated compounds inside the calibration chamber, using Tenax-filled desorption tubes and a low flow personal air sampling pump. Versatile, easy and rapid atmospheric monitor (VERAM) devices were employed for the passive sampling of benzene, toluene, ethylbenzene, xylenes, α-pinene, camphene, myrcene, p-cymene, and limonene from air. The RS values obtained for the passive sampling of VOCs, using the developed calibration chamber, were in the range of 1.3-16.0m3day-1 in accordance to previous calibration studies performed for VERAM samplers. The developed calibration chamber provided a continuous flow with a constant concentration of the evaluated compounds that allowed the simultaneous deployment of several samplers for a rapid establishment of RS for a passive sampler type and the easy comparison between different devices.

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Polyurethane foam - air partition coefficients (KPUF-air) for 9 polycyclic aromatic hydrocarbons (PAHs), 10 alkyl-substituted PAHs, 4 organochlorine pesticides (OCPs) and dibenzothiophene were measured as a function of temperature over the range 5 °C-35 °C, using a generator column approach. Enthalpies of PUF-to-air transfer (ΔHPUF-air, kJ/mol) were determined from the slopes of log KPUF-air versus 1000/T (K), and have an average value of 81.2 ± 7.03 kJ/mol. The log KPUF-air values at 22 °C ranged from 4.99 to 7.25. A relationship for log KPUF-air versus log KOA was shown to agree with a previous relationship based on only polychlorinated biphenyls (PCBs) and derived from long-term indoor uptake study experiments. The results also confirm that the existing KOA-based model for predicting log KPUF-air values is accurate. This new information is important in the derivation of uptake profiles and effective air sampling volumes for PUF disk samplers so that results can be reported in units of concentration in air.

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The occurrence of persistent organic pollutants (POPs) in the atmosphere of the near-coast South Atlantic Ocean was studied. Air samples were collected using a high-volume air sampler (filter and polyurethane foam) on board the Argentinean research cruise R/V Puerto Deseado (CONICET). Samples were analyzed for 50 polychlorinated biphenyl (PCBs), 22 organochlorine pesticides (OCPs) and 14 polybrominated diphenyl ethers (PBDEs). These POPs classes showed a trend of decreasing levels from near-shore to open ocean sites. OCPs and PCBs were in the same order of magnitude (2.71-87.1pg/m(3) and 9.56-130pg/m(3), respectively) while PBDEs levels were significantly lower (0.69-2.58pg/m(3)). Dichlorodiphenyltrichloroethanes (DDTs), endosulfans, chlordanes, hexachlorocyclohexanes (HCHs) and heptachlors were between 0.20 and 17.8pg/m(3), while drines and hexachlorobenzene (HCB) were at lower levels (0.28-3.71pg/m(3)). The most frequently detected PCBs were congeners 32, 28, 44, 52, 95, representing >50% of the total. The PBDEs congener pattern was dominated by congener 209 (70%), followed by 47 and 99 (16% and 7%, respectively). Air parcel back trajectories for the study period provided few insights as trajectories mainly stemmed from the open ocean with limited inputs from continental sources. These results indicate that the concentration of POPs (namely PCBs, OCPs, and PBDEs) in air remain elevated in the near-shore environment and then drop-off substantially beyond a distance of about 400km. This has implications for the loading of POPs and delivery to the marine environment in the near coastal zone.

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The Deepwater Horizon (DWH) oil spill in the Gulf of Mexico was the largest maritime oil spill in history resulting in the accumulation of genotoxic substances in the air, soil, and water. This has potential far-reaching health impacts on cleanup field workers and on the populations living in the contaminated coastal areas. We have employed portable airborne particulate matter samplers (SKC Biosampler Impinger) and a genetically engineered bacterial reporter system (umu-ChromoTest from EBPI) to determine levels of genotoxicity of air samples collected from highly contaminated areas of coastal Louisiana including Grand Isle, Port Fourchon, and Elmer's Island in the spring, summer and fall of 2011, 2012, 2013 and 2014. Air samples collected from a non-contaminated area, Sea Rim State Park, Texas, served as a control for background airborne genotoxic particles. In comparison to controls, air samples from the contaminated areas demonstrated highly significant increases in genotoxicity with the highest values registered during the month of July in 2011, 2013, and 2014, in all three locations. This seasonal trend was disrupted in 2012, when the highest genotoxicity values were detected in October, which correlated with hurricane Isaac landfall in late August of 2012, about five weeks before a routine collection of fall air samples. Our data demonstrate: (i) high levels of air genotoxicity in the monitored areas over last four years post DWH oil spill; (ii) airborne particulate genotoxicity peaks in summers and correlates with high temperatures and high humidity; and (iii) this seasonal trend was disrupted by the hurricane Isaac landfall, which further supports the concept of a continuous negative impact of the oil spill in this region.

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Concentration gradients were observed in gas and particulate phases of PCDD/F originating from industrial and vehicular sources in the densely populated tropical Andean city of Manizales, using passive and active air samplers. Preliminary results suggest greater concentrations of dl-PCB in the mostly gaseous fraction (using quarterly passive samplers) and greater concentrations of PCDD/F in the mostly particle fraction (using daily active samplers). Dioxin-like PCB predominance was associated with the semi-volatility property, which depends on ambient temperature. Slight variations of ambient temperature in Manizales during the sampling period (15°C-27°C) may have triggered higher concentrations in all passive samples. This was the first passive air sampling monitoring of PCDD/F conducted in an urban area of Colombia. Passive sampling revealed that PCDD/F in combination with dioxin-like PCB ranged from 16 WHO-TEQ2005/m(3) near industrial sources to 7 WHO-TEQ2005/m(3) in an intermediate zone-a reduction of 56% over 2.8 km. Active sampling of particulate phase PCDD/F and dl-PCB were analyzed in PM10 samples. PCDD/F combined with dl-PCB ranged from 46 WHO-TEQ2005/m(3) near vehicular sources to 8 WHO-TEQ2005/m(3) in the same intermediate zone, a reduction of 83% over 2.6 km. Toxic equivalent quantities in both PCDD/F and dl-PCB decreased toward an intermediate zone of the city. Variations in congener profiles were consistent with variations expected from nearby sources, such as a secondary metallurgy plant, areas of concentrated vehicular emissions and a municipal solid waste incinerator (MSWI). These variations in congener profile measurements of dioxins and dl-PCBs in passive and active samples can be partly explained by congener variations expected from the various sources.

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OBJECTIVE: Asbestos is an established human carcinogen and has been identified at 16 of 26 Jamaican hospitals surveyed. We sought to determine if hospital employees are exposed and if current asbestos exposure in Jamaican hospitals differed by job category. METHOD: At two of the largest hospitals with more than 10 permanent maintenance workers and where over 67% of bulk samples analysed contained asbestos, three groups of employees selected by stratified random sampling participated in a personal air sampling study for asbestos. One hundred and thirty-two personal air samples and 32 area samples were collected and analysed for asbestos fibres utilizing phase contrast microscopy (PCM) and transmission electron microscopy (TEM). RESULTS: Twenty-four (14.6%) air samples had fibre counts above the limit of detection (LOD) for the analytical method (PCM), ranging from 0.002f/cc to 0.013 f/cc. The fibres met the dimensional characteristics ofasbestos fibres. There was no difference in the median fibre concentration to which the groups of employees were exposed. Further testing of samples which had fibre counts above the LOD using TEM confirmed that the fibres were not asbestos. CONCLUSION: Despite not finding asbestos fibres in the air samples, most of the asbestos containing building material (ACBM) found in the hospitals was friable and in a poor condition indicative of fibre release. We recommend an ongoing monitoring programme for airborne asbestos fibres in hospitals until an abatement programme can be undertaken by the regulatory agencies in the country.

OBJETIVO: El asbesto, también llamado amianto, es un carcinógeno humano conocido, y ha sido identificado en 16 de 26 hospitales jamaicanos investigados. El presente trabajo tuvo por objeto determinar si los empleados del hospital están expuestos al asbesto, y si la exposición actual de asbesto en hospitales jamaicanos difiere según la categoría del trabajo. MÉTODO: En dos de los hospitales más grandes con más de 10 obreros de mantenimiento permanentes y dónde más del 67% de las muestras a granel analizadas contenían asbesto, tres grupos de empleados seleccionados por muestreo aleatorio estratificado participaron en una investigación de muestreo de aire personal en busca de asbesto. Ciento treinta y dos muestras de aire personal y 32 muestras de área fueron recogidas y analizadas en busca de fibras de asbesto, utilizando microscopía de contraste de fases (MCF) y microscopía electrónica de transmisión (MET). RESULTADOS: Veinticuatro (14.6%) muestras de aire tuvieron un conteo de fibras por encima del límite de detección (LDD) para el método analítico (MCF), que fluctuaba de 0.002 f/cc a 0.013 f/cc. Las fibras correspondían a las características dimensionales de las fibras de asbesto. No hubo diferencias en la concentración mediana de las fibras a la que los grupos de empleados estaban expuestos. Pruebas posteriores con las muestras que arrojaron conteos de fibras por encima del LDD usando la MET, confirmaron que las fibras no eran de asbesto. CONCLUSIÓN: A pesar de que no se encontraron fibras de asbesto en las muestras de aire, la mayor parte de los materiales de construcción que contienen asbesto (ACBM) hallados en los hospitales eran friables y estaban en mal estado, dando ya señales de desprendimiento de fibras. Se recomienda un programa de monitoreo de fibras de asbesto suspendidas en el aire en los hospitales hasta que pueda emprenderse un programa de eliminación de las mismas por parte de las agencias reguladoras del país.

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