High Levels Of Volatile Organic Compounds Research Articles

Volatile Organic Compounds in Disposable Diapers and Baby Wipes in the US: A Survey of Products and Health Risks.

Many thousands of diapers are worn by young children and the elderly, who have thin and sensitive skin that is highly vulnerable to chemicals, including volatile organic compounds (VOCs) that may be ingredients of these products or present as inadvertent or residual components. The levels and potential health risks of VOCs in diapers have not been reported previously. In this study, we collected 31 disposable hygiene products in the US market based on market share and analyzed 98 target VOCs using purge and trap sampling and thermal desorption/gas chromatography/mass spectrometer analysis. Exposures and risks were modeled using reasonable upper level exposure scenarios. Adult diapers contained the highest total target VOC concentration (median level of 23.5 μg/g), and the predominant VOCs were alkanes. In some diapers, the estimated noncancer risk from these VOCs was sometimes very large (hazard quotient of 1609) due to n-heptane. Baby diapers contained several known or suspected carcinogens, including benzene and 1,4-dioxane, and the lifetime cancer risk from some diapers approached 1 per million under a worst-case scenario. Store-brand products had higher levels of VOCs than generic brands, and products labeled "organic" or "for sensitive skin" did not necessarily have lower levels. Our results show that toxic VOCs were found in all tested disposable diapers and wipes at trace levels, and risks from using some diapers in high use exposure scenarios are high enough to warrant additional attention and possibly corrective measures. We recommend eliminating and monitoring toxic ingredients and disclosing all chemicals that may be in these products.

Volatile organic compounds and metals/metalloids exposure in children after e-waste control: Implications for priority control pollutants and exposure mitigation measures

The decade-long effort to control e-waste in China has made significant progress from haphazard disposal to organized recycling, but environmental research suggests that exposure to volatile organic compounds (VOCs) and metals/metalloids (MeTs) still poses plausible health risks. To investigate the exposure risk faced by children and identify corresponding priority control chemicals, we evaluated the carcinogenic risk (CR), non-CR, and oxidative DNA damage risks of VOCs and MeTs exposure in 673 children from an e-waste recycling area (ER) by measuring urinary exposure biomarker levels. The ER children were generally exposed to high levels of VOCs and MeTs. We observed distinctive VOCs exposure profiles in ER children. In particular, the 1,2-dichloroethane/ethylbenzene ratio and 1,2-dichloroethane were promising diagnostic indexes for identifying e-waste pollution due to their high accuracy (91.4%) in predicting e-waste exposure. Exposure to acrolein, benzene, 1,3-butadiene, 1,2-dichloroethane, acrylamide, acrylonitrile, arsenic, vanadium, copper, and lead posed considerable CR or/and non-CR and oxidative DNA damage risks to children, while changing personal lifestyles, especially enhancing daily physical exercise, may facilitate mitigating these chemical exposure risks. These findings highlight that the exposure risk of some VOCs and MeTs is still non-negligible in regulated ER, and these hazardous chemicals should be controlled as priorities.

Continuous monitoring of volatile organic compounds through sensorization. Automatic sampling during pollution/odour/nuisance episodic events

Volatile organic compounds (VOCs) are a highly diverse class of chemical contaminants and between 50 and 300 of them may be found in ambient air. In urbanized areas, VOCs are emitted from industrial activities, as well as from vehicle-related and combustion sources. VOCs outdoors can be detected in a broad range of concentrations, usually varying seasonally. The presence of VOCs at relatively high concentrations has been related to poor air quality, discomfort and odorous nuisances. Additionally, they can have negative health effects to the human organism. Hence, in locations where recurrent sporadic situations of high VOCs levels take place, episodic samples' evaluation is necessary instead of 24 h or longer sampling period's evaluations. The use of commercially available metal oxide semiconductor gas sensors for a continuous monitoring of VOCs concentrations in outdoor air is an interesting and innovative technology. Additionally, the use of these sensors for the activation of a VOCs sampler when episodic events of nuisance/odorous annoyance occur was successfully evaluated. The sensor activation is induced by higher VOCs concentrations from a wide number of VOC chemical families. Two sensor stations, developed at our laboratory and provided with sampling pumps, were located in the municipality of Santa Margarida i els Monjos (Catalunya, Spain) in January 2021. The stations started recording data continuously from two different types of VOCs sensors, temperature, relative humidity and pressure in 1.5-min periods. Automatic VOCs sampling was conducted, using multi-sorbent bed tubes, during the months of June–July when the sensors electronic values exceeded a set point value. Samples were analysed through TD-GC/MS. TVOC concentrations in episode samples ranged between 78-669 and 12–159 μg m−3 in Site 1 and Site 2, respectively. Although TVOC concentrations were not high in all cases, relevant concentrations of chloroform were observed, especially in Site 1, with concentrations ranging from 19 to 159 μg m−3.

Upward trend and formation of surface ozone in the Guanzhong Basin, Northwest China

Increase trend of surface ozone (O3) was observed in the Guanzhong Basin (GZB) from 2014 to 2020 with growth rates of 3.9–6.4 μg m−3 yr−1 for the maximum daily average 8 h (MDA8) O3 concentrations. To further understand the formation of O3, investigation of volatile organic compounds (VOCs) was carried out in the summer of 2018. High levels of VOCs were observed in both residential area and industrialized cities. Elevated concentrations of none-methane Hydrocarbon (NMHCs) were observed in rush hours, which indicated dominated roles of traffic activities on the loading of ambient VOCs. In the nighttime, both of NMHCs and oxygenated VOCs (OVOCs) were raised, and the peaks of VOCs kept pace with accumulation of O3. Wind field indicated that northward and westward air mass, which passed through the remote forest and industrial area in east of the GZB, was responsible to elevated ambient VOCs in the GZB. Traffic emission, fuel evaporation, and solvent using were key contributors to ambient NMHCs, while solvent using and secondary formation dominated the loading of OVOCs. The present study indicated that both local management and regional collaborative control on active VOCs species from typical sources is urgently needed in GZB.

Intercropping With Peppermint Increases Ground Dwelling Insect and Pollinator Abundance and Decreases Drosophila suzukii in Fruit

Intercropping can be used to reduce pest insects within agricultural systems, e.g., through deterring pests directly or by increasing habitat for their natural enemies. For example, plant produced volatile organic compounds (VOCs) can deter or confuse host-finding by insects through olfactory disruption. Drosophila suzukii is an invasive fruit fly of agricultural concern as it can lay its eggs in both ripening and fresh fruits and, uses olfactory cues to identify its wide range of host plants. Peppermint plants (Mentha × piperita) produce high levels of VOCs while growing and may, therefore, be suitable as an intercrop to reduce D. suzukii infestations in the field, as peppermint essential oil VOCs have previously been shown to deter D. suzukii in olfactory trials. We conducted a field intercropping experiment to evaluate the effectiveness of peppermint plants compared to traditional ryegrass/clover mixes in reducing D. suzukii oviposition in the field, and the effect of peppermint intercrops on other invertebrates. In the field, we monitored sentinel fruit baits weekly for D. suzukii infestation. Additionally, we monitored intercropping effects on the invertebrate community through weekly pitfall trap collection and through a pollinator point survey. We monitored for local, farm level presence of D. suzukii through apple cider vinegar traps within crop fields and along hedgerows and found high abundance of D. suzukii (>3,000 individuals trapped). Peppermint intercrops had fewer D. suzukii emerge from fruit baits and supported greater beneficial insect abundance (predators and pollinators) compared to ryegrass/clover. However, levels of D. suzukii were low across both intercrop types. Overall, we found that peppermint intercrops could be a potential aromatic intercrop used to reduce D. suzukii adult emergence from fruit compared to conventional ryegrass/clover mixes, however this trial should be replicated over multiple growing seasons, geographic locations, and host fruits. Furthermore, further study should determine the effects of the intercrop on the focal crop of interest.

Measurement and minutely-resolved source apportionment of ambient VOCs in a corridor city during 2019 China International Import Expo episode

In this study, real-time measurement of Volatile Organic Compounds (VOCs) was conducted at an urban site in Changzhou, a typical corridor city in the Yangtze River Delta (YRD) region in China, by Proton−Transfer−Reaction Time−of−Flight Mass Spectrometry (PTR−ToF−MS) during 2019 China International Import Expo (CIIE) episode. An improved method based on Air Quality Index (AQI) value is applied to identify polluted and clean periods. Diurnal pattern of VOC levels revealed elevated photochemical reactivity during polluted periods. Five VOC sources were identified by Positive Matrix Factorization (PMF) model, including secondary formation (22.71 ± 12.33%), biogenic (21.50% ± 11.76%), solvent usage (20.50 ± 10.07%), vehicle exhaust (18.32 ± 8.32%), and industrial process and fuel usage (16.96 ± 13.21%). The mean contribution of vehicular exhaust was 10.84% higher during the nighttime than the daytime under polluted days. The biogenic source contributed more during clean periods, while the secondary formation presented the opposite. Spatial analysis displayed that the VOC concentration was higher in the S and SSE. In terms of the regional transport, short-distance air masses from the northeast and the south within the YRD region led to high VOC levels and biogenic VOC derived from the ocean might affect the entire region. Stringent emission control policies enforced over the YRD for 2019 CIIE provided an excellent opportunity to determine the source-receptor response. As joint control area, the VOC level of Changzhou exhibited a substantial reduction and the VOC amounts emitted by solvent usage showed the biggest decrease (−58%). The findings of this study highlight the superiority of high time-resolved data in identifying the dynamic variation pattern (with the change of time and wind) of VOC levels and emission intensities.

Pediatric Asthma Attack and Home Paint Exposure.

Although asthma mortality has been declining for the past several decades, asthma morbidity is on the rise, largely due to deteriorating indoor air quality and comorbidities, such as allergies. Consumer products and building materials including paints emit volatile organic compounds (VOCs), such as propylene glycol (PG), which is shown to dehydrate respiratory tracts and can contributor to airway remodeling. We hypothesize that paint exposure increases the risk of asthma attacks among children because high levels of VOCs persist indoors for many weeks after painting. Children 1–15 years old visiting two of the University of Miami general pediatric clinics were screened for their history of asthma and paint exposure by interviewing their parents and/or guardians accompanying them to the clinic. They were also asked questions about asthma diagnosis, severity of asthma and allergies and their sociodemographics. The risk of asthma attack among asthmatic children was modeled with respect to paint exposure adjusting for potential confounders using multivariate logistic regressions. Of 163 children, 36 (22%) reported physician-diagnosed asthma and of these, 13 (33%) had an asthma attack during the last one year. Paint exposure was marginally significant in the univariate analysis (OR = 4.04; 95% CI = 0.90–18.87; p < 0.1). However, exposed asthmatic children were 10 times more likely to experience an asthma attack than unexposed asthmatic children (OR = 10.49; CI = 1.16–94.85, p < 0.05) when adjusted for other risk factors. Given paint is one of the sources of indoor VOCs, multiple strategies are warranted to manage the health effects of VOC exposure from paint, including the use of zero-VOC water-based paint, exposure avoidance and clinical interventions.

Laboratory Estimation of Occupational Exposures to Volatile Organic Compounds During Nail Polish Application.

In the United States, there are more than 120,000 nail salons in which workers could be potentially exposed to a number of volatile organic compounds (VOCs) used in various procedures. Measuring workers exposure in the field is time-consuming and could be very expensive. The purpose of this study was to estimate the VOC levels in the proximity of workers in nail salons through simulating the application process of some popular nail polishes in a laboratory chamber. The worst-case scenario was defined as a worker's exposure during nail polish application to one set of fingernails every 15 minutes for an 8-hour shift (total nail sets = 32). Nail polish was applied on paper plates in a flow-controlled test chamber. Air was sampled during the application of five different nail polishes for 8 hours using passive air samplers and the experiment was triplicated. Passive samplers were used for VOCs and formaldehyde. In this worst-case scenario setting, a total of 17 VOCs were detected, with eight that were found in all the samples. The mean concentration of butyl acetate (161-330 ppm, parts per million) and ethyl acetate (440 ppm) exceeded the threshold limit value (TLV) of 150 ppm and 400 ppm, respectively. Formaldehyde was analyzed separately and the mean concentrations exceeded the TLV of 0.10 ppm in all types of nail polish, ranging from 0.12 ppm to 0.22 ppm. Occupational safety and health professionals could use these data to increase awareness of workers' potential exposure to high levels of VOCs in nail salons and recommend practical measures to reduce potential exposures.

Ambient Volatile Organic Compounds and Racial/Ethnic Disparities in Gestational Diabetes Mellitus: Are Asian/Pacific Islander Women at Greater Risk?

US Asian/Pacific Islander (API) communities experience high air pollution levels. APIs may be predisposed to pancreatic β-cell dysfunction and have the highest prevalence of gestational diabetes mellitus (GDM) compared with other racial/ethnic groups. Exposure to high levels of volatile organic compounds (VOCs) impairs pancreatic β-cell function, leading to insulin resistance, but racial/ethnic differences in this association are unexamined. We analyzed singleton deliveries (n = 220,065) from the Consortium on Safe Labor (2002-2008). Exposure to 14 VOCs in each hospital referral region was based on modified Community Multiscale Air Quality models. Logistic regression estimated odds ratios for GDM associated with high (≥75th percentile) versus low (<75th percentile) VOC exposure 3 months before conception and during the first trimester of pregnancy. Preconception and first-trimester exposure to high VOC levels was associated with increased odds of GDM among whites and APIs. GDM risk was significantly higher for APIs than whites for most VOCs. Preconception benzene exposure was associated with 29% (95% confidence interval: 12, 47) increased odds of GDM among whites compared with 45% (95% confidence interval: 16, 81) increased odds among APIs. These findings highlight environmental health disparities affecting pregnant women. Increased focus on GDM risk in US API communities is warranted.

Characterization and cancer risk assessment of VOCs in home and school environments in gran La Plata, Argentina.

Three areas are highlighted in Gran La Plata, Argentina: industrial, urban, and residential. In this work, the levels of volatile organic compounds (VOCs) in indoor air of homes and schools in those areas were analyzed, through the use of passive monitors. The study period is between 2007 and 2010. Higher levels of VOCs were found in homes and schools in the industrial zone, higher than the levels corresponding to urban and residential. Taking into account the relationship between indoor and outdoor levels of VOCs, they have ratios (I/O) between 1.5 and 10 are evidenced contributions of emission sources of VOCs both indoor and outdoor. Complementarily, we estimated the life time cancer risk (LCR) for benzene, styrene, trichloroethylene, and tetrachloroethylene in children who spend their time mostly in such indoor environments. The results show high LCR values for benzene, which exceed acceptable values for the US EPA.

Evolution process and sources of ambient volatile organic compounds during a severe haze event in Beijing, China

108 ambient volatile organic compounds (VOCs) were measured continuously at a time resolution of an hour using an online gas chromatography–frame ionization detector/mass spectrometry (GC–FID/MS) in October 2014 in Beijing, and positive matrix factorization (PMF) was performed with online data. The evolution process and causes for high levels of VOCs during a haze event were investigated through comprehensive analysis. Results show that mixing ratios of VOCs during the haze event (89.29 ppbv) were 2 to 5 times as that in non-haze days, There was a distinct accumulation process of VOCs at the beginning of the haze event, and the mixing ratios of VOCs maintained at the high levels until to the end of pollution when the mixing ratios of ambient VOCs recovered to the normal concentration levels in a few hours. Some reactive and toxic species increased remarkably as well, which indicates a potential health risk to the public in terms of VOCs. Eight sources were resolved by PMF, and results revealed gasoline exhaust was the largest contributor (32–46%) to the ambient VOCs in Beijing. Emissions of gasoline exhaust surged from 13.46 to 40.36 ppbv, with a similar variation pattern to total VOCs, indicating that high levels of VOCs were largely driven to by expanded vehicular emissions. Emissions of biomass burning also increased noticeably (from 2.32 to 11.12 ppbv), and backward trajectories analysis indicated regional transport of biomass burning emissions. Our findings suggested that extremely high levels of VOCs during the haze event was primarily attributed to vehicular emissions, biomass burning and regional transport, as well as stationary synoptic conditions.

Determination of volatile organic compounds from biowaste and co-fermentation biogas plants by single-sorbent adsorption

Characterisation of biogases is normally dedicated to the online monitoring of the major components methane and carbon dioxide and, to a lesser extent, to the determination of ammonia and hydrogen sulphide. For the case of Volatile Organic Compounds (VOCs), much less attention is usually paid, since such compounds are normally removed during gas conditioning and with exception of sulphur compounds and siloxanes represent a rather low risk to conventional downstream devices but could be a hindrance for fuel cells. However, there is very little information in the literature about the type of substances found in biogases generated from biowaste or co-fermentation plants and their concentration fluctuations. The main aim of this study was to provide information about the time dependencies of the VOCs in three biogas plants spread out through Germany from autumn until summer, which have different process control, in order to assess their potential as biofuels. Additionally, this study was an attempt to establish a correlation between the nature of the substrates used in the biogas plants and the composition of the VOCs present in the gas phase. Significant time-dependent variations in concentration were observed for most VOCs but only small changes in composition were observed. In general, terpenes and ketones appeared as the predominant VOCs in biogas. Although for substances such as esters, sulphur-organic compounds and siloxanes the average concentrations observed were rather low, they exhibited significant concentration peaks. The second biogas plant which operates with dry fermentation was found to contain the highest levels of VOCs. The amount of total volatile organic compounds (TVOCs) for the first, second and third biogas plants ranged from 35 to 259 mg Nm−3, 291–1731 mg Nm−3 and 84–528 mg Nm−3, respectively.

Experimental Measurements of VOC and Radon in Two Romanian Classrooms

The present study reports by experimental measurements the levels of volatile organic compounds (VOC) and radon concentrations in two high school classrooms. The difference between the two classrooms abbreviated as S7 and S8 is the presence of a mechanical ventilation system in one of them (S8). The topic is of high importance as the indoor air quality (IAQ) can affect the health and learning performance of the pupils. VOC and RADON have a substantial weight of IAQ and a study of theirs level can help us to better understand at what levels the children are exposed daily. The two mentioned classroom have suffered recently a massive renovation. The classroom with the ventilation system was mounted with variable flow of fresh air, while the other one relies only on natural ventilation by opening the windows. In S8 several test were done for different fresh air ventilation rates. The conclusions were that in the classroom S7 there were measured high levels of VOC and radon, higher than the maximum admissible which is a serious problem. On the other hand, in the classroom S8 for all the different air rates the values were very low, thus creating a healthy and comfortable environment for the learning process. In this article we raise again the problem of lack of a mechanical ventilation system in all Romanian schools. Due to thermal rehabilitation of the buildings the building is air sealed with negative impact on the introduced fresh air. Moreover, the high number of occupants in the classroom and the renovation of classroom have negative influence on all indoor pollutants levels. The only solution to these problems is a correct design of a school or to install other ways to mechanically introduce the fresh air.

Head Space—Solid Phase Micro Extraction Profile of Volatile Organic Compounds Emitted from Parquet Samples

The potential health risks posed by volatile organic compounds (VOCs) in homes are of concern. There is little information on indoor VOC emissions from wood flooring, called parquet. Six parquet samples were examined for VOCs in this preliminary study using Head Space—Solid Phase Micro Extraction (SPME) gas chromatography, a powerful and versatile analytical method which has been only minimally employed previously in wood chemistry. Prefinished composite samples released the highest levels of VOCs, mainly due to adhesives and finishes, with acetic acid the main component released from the oak component. As some VOCs from parquet present a health hazard, more comprehensive studies employing the SPME technique described herein are needed.

Underestimated public health risks caused by overestimated VOC removal in wastewater treatment processes

The uncontrolled release of volatile organic compounds (VOCs) from wastewater treatment plants (WWTPs) and the adverse health effects on the public have been of increasing concern. In this study, a lab-scale bioreactor was prepared to analyze the mass distribution of three aromatic (benzene, toluene, and xylenes) and four chlorinated VOCs (chloroform, carbon tetrachloride, trichloroethylene, and tetrachloroethylene) among the air, water and sludge phases in wastewater treatment processes. The VOC distribution through a full-scale WWTP in northern China was further investigated with respect to the effects of seasonal temperature variations and treatment technologies, followed by the cancer risk assessment using a steady-state Gaussian plume model (Industrial Source Complex) to simulate the atmospheric behaviors of the VOCs emitted from the WWTP. It was found that three aromatic hydrocarbons, notably benzene, were more readily released from the wastewater into the atmosphere, whereas the chlorinated compounds except chloroform were mainly present in the water phase through the treatment processes. The primary clarifier was the technology releasing high levels of VOCs into the atmosphere from the wastewater. The extents of volatilization or biodegradation, two important mechanisms to remove VOCs from wastewater, appeared to be determined by the physicochemical characteristics of the compounds, as the influence of treatment technologies (e.g., aeration) and seasonal temperature variations was rather limited. More importantly, the people living in the areas even more than 4 km away from the WWTP were still potentially exposed to cancer risks exceeding the regulatory threshold limit. The findings described the complex nature of VOC emissions from WWTPs and quantitatively indicated that the associated health impacts on the public near the WWTPs could be severely underestimated, whereas their treatment efficiencies by wastewater treatment technologies were overestimated. Instead of fully controlling the VOC release from WWTPs, the identification and abatement of important VOC species with regard to the atmospheric emission and health concerns is one possible alternative approach to effectively minimize the environmental and public health impacts by VOCs released from this particular source.

Effect of exposure to volatile organic compounds (VOCs) on inflammatory response in gas station attendant.

IntroductionVolatile Organic Compounds (VOCs) exposition causes multiple chemical sensitivity reactions in human. The exposures of human to VOC environments are associated with an enhanced inflammatory response. The occupational exposures of VOCs and inflammatory responses in gas station attendant not have been reported.AimEvaluate the inflammatory markers plasma concentrations in gas station attendants.Materials and Methods20 gas station attendants who are occupational exposed to high VOC levels (VOC group), and 16 controls individuals (CT group) who are not occupational exposed to VOC. Serum inflammatory markers interleukin (IL)‐8, IL‐1β, IL‐6, IL‐10, IL‐12 and tumor necrosis factor‐alpha (TNF‐α), were measured by flow cytometry using the Human Inflammation Kit BD Cytometric Bead Array (CBA).ResultsIndividuals were 20 to 70 years of age, and those on VOC group had a mean of 12 years working at gas station. Multivariate linear regression model showed that VOCs exposure influenced significantly IL‐12 plasma concentration in gas station attendants (Coef. 1170.44; p=0.007) adjusted to age and smoking. To confirm that result, the IL‐12 concentration was significantly higher on VOC group (1609±250) than CT (720±247; p=0.018).ConclusionOur findings show that occupational exposed to VOC from gas stations are associated with increased levels of inflammation marker related to cytotoxic response, which may be related to reactions to chemicals in human.

Habitation of volatile organic compounds (VOCs) in the aura of Agra the city of Taj Mahal

When speaking about harm to the human body in the term of pollution, indoor pollution is equally harmful as the outdoor pollution. Volatile Organic Compounds contribute to the toxic oxidants which are harmful to the ecosystem, human health and atmosphere. Volatile organic compounds (VOCs) are major group of air pollutants which play critical role in atmospheric chemistry. It contributes to toxic oxidants which are harmful to ecosystem human health and atmosphere. A sampling program was conducted to determine volatile organic compounds (VOCs) levels in the aura of the Agra (India) during day time and overnight between mid-September and mid-October 2010. Sampling sites were selected at residential area and industrial area in Agra. Samples were analyzed for benzene, toluene, ethylenebenzene and o-xylene. The day-and-night differences and day-to-day variations in the concentrations of four selected species were investigated and the effects of several factors such as metrological parameters, sources and transport characteristics on them, were studied. A back trajectory analysis showed that relatively higher levels of VOCs were related to long-range transport of pollutants from polluted area. The vertical motions of air masses also had a large impact on the variations of the level of VOCs.

Pollution characteristics of ambient volatile organic compounds (VOCs) in the southeast coastal cities of China

With the rapid urbanization, the southeast coastal cities of China are facing increasing air pollution in the past decades. Large emissions of VOCs from vehicles and petrochemical factories have contributed greatly to the local air quality deterioration. Investigating the pollution characteristics of VOCs is of great significance to the environmental risk assessment and air quality improvement. Ambient VOC samples were collected simultaneously from nine coastal cities of southeast China using the Tedlar bags, and were subsequently preprocessed and analyzed using a cryogenic preconcentrator and a gas chromatography-mass spectrometry system, respectively. VOC compositions, spatial distributions, seasonal variations and ozone formation potentials (OPFs) were discussed. Results showed that methylene chloride, toluene, isopropyl alcohol and n-hexane were most abundant species, and oxygenated compounds, aromatics and halogenated hydrocarbons were most abundant chemical classes (62.5-95.6% of TVOCs). Both industrial and vehicular exhausts might contribute greatly to the VOC emissions. The VOC levels in the southeast coastal cities of China were sufficiently high (e.g., 6.5 μg m(-3) for benzene) to pose a health risk to local people. A more serious pollution state was found in the southern cities of the study region, while higher VOC levels were usually observed in winter. The B/T ratio (0.26 ± 0.09) was lower than the typical ratio (ca. 0.6) for roadside samples, while the B/E (1.6-7.6) and T/E (7.2-26.8) ratios were higher than other cities around the world, which indicated a unique emission profile in the study region. Besides, analysis on ozone formation potentials (OFPs) indicated that toluene was the most important species in ozone production with the accountabilities for total OFPs of 22.6 to 59.6%.

Characterization and health risk assessment of VOCs in occupational environments in Buenos Aires, Argentina

To detect volatile organic compounds (VOCs) in indoor air in small enterprises in La Plata city and surrounding areas, sampling was conducted using passive diffusion monitors (3M-3500) and analysis of the samples were performed byCG-FID. Analytic methodology was optimized for 23 VOCs (n-alkanes, cycloalkanes, aromatic and chlorinated compounds, ketones and terpenes compounds) by determining the recovery factor and detection limit for each analyte. Different recovery values were obtained by desorbing with a mixture of dichloromethane: methanol (50:50), with a standard deviation lower than 5%. Enterprise analyzed included chemical analysis laboratories, sewing workrooms, electromechanical repair and car painting centers, take away food shops, and a photocopy center. The highest levels of VOCs were found to be in electromechanical repair and car painting centers (hexane, BTEX, CHCl3, CCl4) followed by chemical analysis laboratories and sewing workrooms. Cancer and noncancer risks were assessed using conventional approaches (HQ and LCR, US EPA) using the benzene, trichloroethylene, chloroform for cancer risk, and toluene, xylene and n-hexane, for noncancer risks as markers. The results showed different LCR for benzene and trichloroethylene between the different indoor environments analyzed (electromechanical repair and car painting center≫others) and chloroform (laboratory>others), but comparing with the results obtained by other research, are in similar order of magnitude for equivalents activities. Similar finding were founded for HQ. Comparing these results with the worker protection legislation the electromechanical repair and car painting center and chemical analysis laboratories are close to the limits advised by OSHA and ACGIH. These facts show the importance of the use of abatement technologies for the complete reduction of VOCs levels, to mitigate their impact in the worker’s health and their venting to the atmosphere.

Contrasting winter and summer VOC mixing ratios at a forest site in the Western Mediterranean Basin: the effect of local biogenic emissions

Abstract. Atmospheric volatile organic compounds (VOCs) are involved in ozone and aerosol generation, thus having implications for air quality and climate. VOCs and their emissions by vegetation also have important ecological roles as they can protect plants from stresses and act as communication cues between plants and between plants and animals. In spite of these key environmental and biological roles, the reports on seasonal and daily VOC mixing ratios in the literature for Mediterranean natural environments are scarce. We conducted seasonal (winter and summer) measurements of VOC mixing ratios in an elevated (720 m a.s.l.) holm oak Mediterranean forest site near the metropolitan area of Barcelona (NE Iberian Peninsula). Methanol was the most abundant compound among all the VOCs measured in both seasons. While aromatic VOCs showed almost no seasonal variability, short-chain oxygenated VOCs presented higher mixing ratios in summer, presumably due to greater emission by vegetation and increased photochemistry, both enhanced by the high temperatures and solar radiation in summer. Isoprenoid VOCs showed the biggest seasonal change in mixing ratios: they increased by one order of magnitude in summer, as a result of the vegetation's greater physiological activity and emission rates. The maximum diurnal concentrations of ozone increased in summer too, most likely due to more intense photochemical activity and the higher levels of VOCs in the air. The daily variation of VOC mixing ratios was mainly governed by the wind regime of the mountain, as the majority of the VOC species analyzed followed a very similar diel cycle. Mountain and sea breezes that develop after sunrise advect polluted air masses to the mountain. These polluted air masses had previously passed over the urban and industrial areas surrounding the Barcelona metropolitan area, where they were enriched in NOx and in VOCs of biotic and abiotic origin. Moreover, these polluted air masses receive additional biogenic VOCs emitted in the local valley by the vegetation, thus enhancing O3 formation in this forested site. The only VOC species that showed a somewhat different daily pattern were monoterpenes because of their local biogenic emission. Isoprene also followed in part the daily pattern of monoterpenes, but only in summer when its biotic sources were stronger. The increase by one order of magnitude in the concentrations of these volatile isoprenoids highlights the importance of local biogenic summer emissions in these Mediterranean forested areas which also receive polluted air masses from nearby or distant anthropic sources.