Regional assessment of ambient volatile organic compounds from biopharmaceutical R&D complex

An emission model for inhalable chemicals from children's play mats based on partition coefficients

Inhalable chemicals found in children's play mats can be slowly released into indoor environments and consequently threaten human health. In this study, the partition coefficients of seven inhalable chemicals between play mats and air were calculated by headspace gas chromatography-mass spectrometry based on the law of conservation of mass and the principle of equilibrium of headspace bottles. Furthermore, an emission source model for the residual ratio of the inhalable chemicals in play mats was established. Most substances found in play mats have large partition coefficients owing to the complex void structure of the mats, which adsorbs a large number of organic pollutants. The partition coefficient is not only related to the boiling point and environmental temperature, but also the specific material and the adsorption of the organic pollutant onto the material. The emission source model for children's play mats developed in this study can characterize the decay of the inhalable chemicals over time. The data showed that after eight days of placing the play mat in a ventilated environment, the residual ratio of seven inhalable chemicals did not exceed 15 %.

VOC emitted by biopharmaceutical industries: Source profiles, health risks, and secondary pollution

The biopharmaceutical industry contributes substantially to volatile organic compounds (VOCs) emissions, causing growing concerns and social developmental conflicts. This study conducted an on-site investigation of the process-based emission of VOCs from three biopharmaceutical enterprises. In the workshops of the three enterprises, 26 VOCs were detected, which could be sorted into 4 classes: hydrocarbons, aromatic hydrocarbons, oxygen-containing compounds, and nitrogen-containing compounds. Ketones were the main components of waste gases, accounting for 44.13%-77.85% of the overall VOCs. Process-based source profiles were compiled for each process unit, with the fermentation and extraction units of tiamulin fumarate being the main source of VOC emissions. Dimethyl heptanone, vinyl acetate, diethylamine, propylene glycol methyl ether (PGME), and benzene were screened as priority pollutants through a fuzzy comprehensive evaluation system. Ground level concentration simulation results of the Gauss plume diffusion model demonstrated that the diffusivity of VOCs in the atmosphere was relatively high, indicating potential non-carcinogenic and carcinogenic risks 1.5-2 km downwind. Furthermore, the process-based formation potentials of ozone and secondary organic aerosols (SOAs) were determined and indicated that N-methyl-2-pyrrolidone, dimethyl heptanone, and PGME should be preferentially controlled to reduce the ozone formation potential, whereas the control of benzene and chlorobenzene should be prioritized to reduce the generation of SOAs. Our results provide a basis for understanding the characteristics of VOC emission by biopharmaceutical industries and their diffusion, potentially allowing the development of measures to reduce health risks and secondary pollution.

Fugitive emissions of volatile organic compounds from the pharmaceutical industry in China based on leak detection and repair monitoring, atmospheric prediction, and health risk assessment

In this study, a leak detection and repair program was conducted on five pharmaceutical factories in China to analyze the volatile organic compounds (VOCs) emission characteristics of leaking equipment. The results indicated that the monitored components were mainly flanges, accounting for 70.23% of the total, and open-ended lines were the components most prone to leaks. The overall percentage of VOCs emissions reduction after the repair was 20.50%, and flanges were the most repairable components, with an average emission reduction of 47.5 kg/a for each flange. In addition, atmospheric predictions were conducted for the VOCs emissions before and after the repair of the components at the research factories. The atmospheric predictions showed that emissions from equipment and facilities have a noticeable impact on VOCs concentration at boundary and the emissions are positively correlated with the pollution source strength. The hazard quotient of the investigated factories was lower than the acceptable risk level set by the US Environmental Protection Agency (EPA). The quantitative assessment of the lifetime cancer risk showed that the risk levels of factories A, C, and D exceeded the EPA's acceptable risk level, and the on-site workers were exposed to inhalation cancer risk.

Process-based VOCs source profiles and contributions to ozone formation and carcinogenic risk in a typical chemical synthesis pharmaceutical industry in China

The chemical synthesis pharmaceutical industry plays an important role in VOCs emissions from industrial sources, which has caused increasing concern. In this study, the process-based pollution characteristics of VOCs from the chemical synthesis pharmaceutical industry were investigated in the Yangtze River Delta, China. A total of 16 samples were collected from 12 process units (including 5 production lines and 2 postprocessing units) and 2 factory boundary sites. 116 VOCs species were analyzed and sorted into 6 classes, including alkanes, alkenes, acetylene, aromatics, halocarbons and oxygenated VOCs (OVOCs). The concentration of stack VOCs was 3.37 × 10⁴ μg·m^-3, while the concentration of fugitive VOCs from other process units ranged from 827 μg·m^-3 to 2.11 × 10⁴ μg·m^-3. Aromatics, halocarbons and OVOCs accounted for a relatively high proportion in all process units. Process-based source profiles of each process unit were compiled. Generally, toluene, dichloromethane, ethanol, methanol and acetone were the most abundant species in all process units. Furthermore, the process-based ozone formation potentials (OFPs) and carcinogenic risk potentials (CRPs) were calculated, suggesting that toluene, methanol, ethanol and m/p-xylene should be preferentially controlled to reduce the OFPs, while acetaldehyde and chloroform were the priority control species to reduce the CRPs. Further discussion showed that ambient VOCs pollution at the factory boundary was affected by both stack and fugitive sources from the production process. The source profiles built in this study are necessary addition to the current profiles and are a good reference to study VOCs emission characteristics from the perspective of the process procedure. The results obtained from this work provide a guidance for effective VOCs abatement strategies and further lay a foundation for related research on VOCs in the chemical synthesis pharmaceutical industry.

Occurrence and distribution of antimicrobial resistance genes in the soil of an industrial park in China: A metagenomics survey

As zoned areas of industries, industrial parks have great impacts on the environment. Several studies have demonstrated that chemical compounds and heavy metals released from industrial parks can contaminate soil, water, and air. However, as an emerging pollutant, antimicrobial resistance genes (ARGs) in industrial parks have not yet been investigated. Here, we collected soil samples from 35 sites in an industrial park in China and applied a metagenomics strategy to profile the ARGs and virulence factors (VFs). We further compared the relative abundance of ARGs between the sites (TZ_31-35) located in a beta-lactam antimicrobial-producing factory and other sites (TZ_1-30) in this industrial park. Metagenomic sequencing and assembly generated 14, 383, 065 contigs and 17, 631, 051 open reading frames (ORFs). Taxonomy annotation revealed Proteobacteria and Actinobacteria as the most abundant phylum and class, respectively. The 32 pathogenic bacterial genera listed in the virulence factor database (VFDB) were all identified from the soil metagenomes in this industrial park. In total, 685,354 ARGs (3.89% of the ORFs) and 272,694 virulence factors (VFs) (1.55% of the ORFs) were annotated. These ARGs exhibited resistance to several critically important antimicrobials, such as rifampins, fluroquinolones, and beta-lactams. In addition, no significant difference in the relative abundance of ARGs was observed between sites TZ_31-35 and TZ_1-30, indicating that ARGs have already disseminated widely in this industrial park. The present study gave us a better understanding of the whole picture of the resistome and virulome in the soil of the industrial park and suggested that we should treat the industrial park as a whole in the surveillance and maintenance of ARGs.

Emission characteristics and associated assessment of volatile organic compounds from process units in a refinery

The accuracy and reliability of volatile organic compound (VOC) emission data are essential for assessing emission characteristics and their potential impact on air quality and human health. This paper describes a new method for determining VOC emission data by multipoint sampling from various process units inside a large-scale refinery. We found that the emission characteristics of various production units were related to the raw materials, products, and production processes. Saturated alkanes accounted for the largest fraction in the continuous catalytic reforming and wastewater treatment units (48.0% and 59.2%, respectively). In the propene recovery unit and catalytic cracking unit, alkenes were the most dominant compounds, and propene provided the largest contributions (57.8% and 23.0%, respectively). In addition, n-decane (12.6%), m,p-xylene (12.4%), and n-nonane (8.9%) were the main species in the normal production process of the delayed coking unit. Assessments of photochemical reactivity and carcinogenic risk were carried out, and the results indicate that VOC emissions from the propene recovery unit and catalytic cracking unit should be controlled to reduce the ozone formation potential; in addition, alkenes are precedent-controlled pollutants. The cancer risk assessments reveal that 1,2-dibromoethane, benzene, 1,2-dichloroethane, and chloroform were the dominant risk contributors, and their values were much higher than the standard threshold value of 1.0 × 10^-6 but lower than the significant risk value defined by the US Supreme Court. Based on the VOC composition and a classification algorithm, the samples were classified into eight main groups that corresponded to different process units in the petroleum refinery. In conclusion, this work provides valuable data for investigating process-specific emission characteristics of VOCs and performing associated assessments of photochemical reactivity and carcinogenic risk in petrochemical refineries.

Profile and source apportionment of volatile organic compounds from a complex industrial park

Industrial emissions, mainly from industrial parks, are important sources of ambient volatile organic compounds (VOCs). Identification of the major sources of VOCs from industrial parks has practical significance in emission reduction. In this study, the major species of VOCs from a residential area located downwind of a complex industrial park were sampled with Tenax absorption tubes and analyzed by thermal desorption coupled with gas chromatography/mass spectrometry (TD-GC/MS). Receptor models of factor analysis with nonnegative constraints (FA-NNC) and positive matrix factorization (PMF) were employed to recognize the potential emission sources, which suggested an association with the production processes in the nearby industrial park. In order to validate the sources, the profiles of VOC emissions of related workshops under actual manufacturing processes were acquired. It was found that xylenes & amines, phenols and esters were the major species of VOCs for the workshops of foundry, refractory materials and printing, respectively. Similarity analysis indicated that the detected profiles of VOC emissions from the dominant industrial types had good correlations with the identified factors from receptor models. Source contributions to VOCs in the receptor region exhibited that foundry production was the primary contributor (56-64%), followed by refractory material production (22-26%) and printing (14-18%). This study provides a strategy for source apportionment of VOCs from a local complex industrial park, which is helpful in the development of targeted control strategies.

Sector-based VOCs emission factors and source profiles for the surface coating industry in the Pearl River Delta region of China

Accurate depiction of VOCs emission characteristics is essential for the formulation of VOCs control strategies. As one of the continuous efforts in improving VOCs emission characterization in the Pearl River Delta (PRD) region, this study targeted on surface coating industry, the most important VOCs emission sources in the PRD. Sectors in analysis included shipbuilding coating, wood furniture coating, metal surface coating, plastic surface coating, automobile coating and fabric surface coating. Sector-based field measurement was conducted to characterize VOCs emission factors and source profiles in the PRD. It was found that the raw material-based VOCs emission factors for these six sectors ranged from 0.34 to 0.58kg VOCs per kg of raw materials (kg·kg^-1) while the emission factors based on the production yield varied from 0.59kg to 13.72t VOCs for each production manufactured. VOCs emission factors of surface coating industry were therefore preferably calculated based on raw materials with low uncertainties. Source profiles differed greatly among different sectors. Aromatic was the largest group for shipbuilding coating, wood furniture coating, metal surface coating and automobile coating while the oxygenated VOCs (OVOCs) were the most abundant in the plastic and fabric surface coating sectors. The major species of aromatic VOCs in each of these six sectors were similar, mainly toluene and m/p-xylene, while the OVOCs varied among the different sectors. VOCs profiles in the three processes of auto industry, i.e., auto coating, auto drying and auto repairing, also showed large variations. The major species in these sectors in the PRD were similar with other places but the proportions of individual compounds were different. Some special components were also detected in the PRD region. This study highlighted the importance of updating local source profiles in a comprehensive and timely manner.

VOCs emission rate estimate for complicated industrial area source using an inverse-dispersion calculation method: A case study on a petroleum refinery in Northern China

This study aimed to apply an inverse-dispersion calculation method (IDM) to estimate the emission rate of volatile organic compounds (VOCs) for the complicated industrial area sources, through a case study on a petroleum refinery in Northern China. The IDM was composed of on-site monitoring of ambient VOCs concentrations and meteorological parameters around the source, calculation of the relationship coefficient γ between the source's emission rate and the ambient VOCs concentration by the ISC3 model, and estimation of the actual VOCs emission rate from the source. Targeting the studied refinery, 10 tests and 8 tests were respectively conducted in March and in June of 2014. The monitoring showed large differences in VOCs concentrations between background and downwind receptors, reaching 59.7 ppbv in March and 248.6 ppbv in June, on average. The VOCs increases at receptors mainly consisted of ethane (3.1%-22.6%), propane (3.8%-11.3%), isobutane (8.5%-10.2%), n-butane (9.9%-13.2%), isopentane (6.1%-12.9%), n-pentane (5.1%-9.7%), propylene (6.1-11.1%) and 1-butylene (1.6%-5.4%). The chemical composition of the VOCs increases in this field monitoring was similar to that of VOCs emissions from China's refineries reported, which revealed that the ambient VOCs increases were predominantly contributed by this refinery. So, we used the ISC3 model to create the relationship coefficient γ for each receptor of each test. In result, the monthly VOCs emissions from this refinery were calculated to be 183.5 ± 89.0 ton in March and 538.3 ± 281.0 ton in June. The estimate in June was greatly higher than in March, chiefly because the higher environmental temperature in summer produced more VOCs emissions from evaporation and fugitive process of the refinery. Finally, the VOCs emission factors (g VOCs/kg crude oil refined) of 0.73 ± 0.34 (in March) and 2.15 ± 1.12 (in June) were deduced for this refinery, being in the same order with previous direct-measurement results (1.08-2.65 g VOCs/kg crude oil refined). An inverse-dispersion calculation method was applied to estimate VOCs emission rate for a petroleum refinery, being 183.5 ton/month (March) and 538.3 ton/month (June).

Atmospheric carbon tetrachloride in rural background and industry surrounded urban areas in Northern Iberian Peninsula: Mixing ratios, trends, and potential sources

Latest investigations on atmospheric carbon tetrachloride (CTC) are focused on its ozone depleting potential, adverse effects on the human health, and radiative efficiency and Global Warming Potential as a greenhouse gas. CTC mixing ratios have been thoroughly studied since its restriction under the Montreal Protocol, mostly in remote areas with the aim of reporting long-term trends after its banning. The observed decrease of the CTC background mixing ratio, however, was not as strong as expected. In order to explain this behavior CTC lifetime should be adjusted by estimating the relative significance of its sinks and by identifying ongoing potential sources. Looking for possible sources, CTC was measured with high-time resolution in two sites in Northern Spain, using auto-GC systems and specifically developed acquisition and processing methodologies. The first site, Bilbao, is an urban area influenced by the surrounding industry, where measurements were performed with GC-MSD for a one-year period (2007-2008). The second site, at Valderejo Natural Park (VNP), is a rural background area where measurements were carried out with GC-FID and covering CTC data a nonsuccessive five-year period (2003-2005, 2010-2011, and 2014-2015years). Median yearly CTC mixing ratios were slightly higher in the urban area (120pptv) than in VNP (80-100pptv). CTC was reported to be well mixed in the atmosphere and no sources were noticed to impact the rural site. The observed long-term trend in VNP was in agreement with the estimated global CTC emissions. In the urban site, apart from industrial and commercial CTC sources, chlorine-bleach products used as cleaning agents were reported as promotors of indoor sources.

Process-specific emission characteristics of volatile organic compounds (VOCs) from petrochemical facilities in the Yangtze River Delta, China

Process-specific emission characteristics of volatile organic compounds (VOCs) from petrochemical facilities were investigated in the Yangtze River Delta, China. Source samples were collected from various process units in the petrochemical, basic chemical, and chlorinated chemical plants, and were measured using gas chromatography-mass spectrometry/flame ionization detection. The results showed that propane (19.9%), propene (11.7%), ethane (9.5%) and i-butane (9.2%) were the most abundant species in the petrochemical plant, with propene at much higher levels than in petrochemical profiles measured in other regions. Styrene (15.3%), toluene (10.3%) and 1,3-butadiene (7.5%) were the major species in the basic chemical industry, while halocarbons, especially dichloromethane (15.2%) and chloromethane (7.5%), were substantial in the chlorinated chemical plant. Composite profiles were calculated using a weight-average approach based on the VOC emission strength of various process units. Emission profiles for an entire petrochemical-related industry were found to be process-oriented and should be established considering the differences in VOC emissions from various manufacturing facilities. The VOC source reactivity and carcinogenic risk potential of each process unit were also calculated in this study, suggesting that process operations mainly producing alkenes should be targeted for possible controls with respect to reducing the ozone formation potential, while process units emitting 1,3-butadiene should be under priority control in terms of toxicity. This provides a basis for further measurements of process-specific VOC emissions from the entire petrochemical industry. Meanwhile, more representative samples should be collected to reduce the large uncertainties.

Spatial distribution and temporal trends of VOCs in a highly industrialized town in Turkey

An extensive monitoring study of volatile organic compounds (VOCs) was conducted at sites across the highly industrialized town of Dilovasi, northern Turkey to determine temporal and spatial trends in pollutant concentrations and relate to the effects of source locations, meteorology, and topography. Two-week passive samplers (Tenax tubes) were deployed at twelve sites from February to December 2012 and analysed using thermal desorption and gas chromatography with mass spectrometric detection (TD-GC-MS). Sampled total VOC (TVOC) levels were highest in the July through October period and were highest at low-altitude sites near industry facilities and vehicle traffic sources (148.3 µg/m(3) at site 11, 154.1 µg/m(3) at site 10) and lowest at high-altitude sites located furthest upwind from industry and traffic sources (78.4 µg/m(3) at site 5 and 78.5 µg/m(3) at site 6). Analysis of "T/B" ratios suggested that contributions to ambient VOC in Dilovasi are dominated by the town's industrial sources. Meteorological conditions and the town's basin topography were also found to significantly influence the city's air quality, with strong winds from the NE observed to correlate with periods of higher sampled TVOC. Compared with other industrialized urban centers, the study revealed that there is significant toluene pollution in Dilovasi and recommended enhanced continuous monitoring at the city's industrial and residential zones.

Industrial sector-based volatile organic compound (VOC) source profiles measured in manufacturing facilities in the Pearl River Delta, China

Industrial sector-based VOC source profiles are reported for the Pearl River Delta (PRD) region, China, based source samples (stack emissions and fugitive emissions) analyzed from sources operating under normal conditions. The industrial sectors considered are printing (letterpress, offset and gravure printing processes), wood furniture coating, shoemaking, paint manufacturing and metal surface coating. More than 250 VOC species were detected following US EPA methods TO-14 and TO-15. The results indicated that benzene and toluene were the major species associated with letterpress printing, while ethyl acetate and isopropyl alcohol were the most abundant compounds of other two printing processes. Acetone and 2-butanone were the major species observed in the shoemaking sector. The source profile patterns were found to be similar for the paint manufacturing, wood furniture coating, and metal surface coating sectors, with aromatics being the most abundant group and oxygenated VOCs (OVOCs) as the second largest contributor in the profiles. While OVOCs were one of the most significant VOC groups detected in these five industrial sectors in the PRD region, they have not been reported in most other source profile studies. Such comparisons with other studies show that there are differences in source profiles for different regions or countries, indicating the importance of developing local source profiles.