Accidental exposure to gas emissions from transit goods treated for pest control

Chemical pollutants in closed environments of transportation and storage of non-dangerous goods - Insufficient legislation, low awareness, and poor practice in Hungary

Several chemical pollutants can accumulate within the closed environments of transportation and storage. Pollutants are mainly residues of pesticides, volatile organic compounds and components of diesel exhaust. The study objectives were to (i) review the regulations relevant to occupational chemical exposures in closed environments of inland transportation and storage; and (ii) explore the practice of preventing these exposures. A systematic search and content analysis of international and Hungarian nation legal documents were carried out. In addition, semi-structured interviews with occupational health and safety (OHS) professionals and warehouse managers were conducted. Analysis of legal documents highlighted the lack of explicit regulations on the investigated problem. The 21 interviews revealed that the participants had limited knowledge about the pollutants; they deemed chemical exposure rare and related health effects negligible. The revealed limitations indicate that this field should be more specifically regulated and OHS professionals should be better informed about these workplace hazards.

Neuropsychological symptoms in workers handling cargo from shipping containers and export logs

PURPOSE

Acute poisonings of workers handling shipping containers by fumigants and other harmful chemicals off-gassed from cargo have been reported but (sub)-chronic neuropsychological effects have not been well studied.

METHODS

This cross-sectional study assessed, using standardised questionnaires, current (past 3-months) neuropsychological symptoms in 274 container handlers, 38 retail workers, 35 fumigators, and 18 log workers, all potentially exposed to fumigants and off-gassed chemicals, and a reference group of 206 construction workers. Prevalence odds ratios (OR), adjusted for age, ethnicity, smoking, alcohol consumption, education, personality traits and BMI, were calculated to assess associations with the total number of symptoms (≥ 3, ≥ 5 or ≥ 10) and specific symptom domains (neurological, psychosomatic, mood, memory/concentration, fatigue, and sleep).

RESULTS

Compared to the reference group, exposed workers were more likely to report ≥ 10 symptoms, statistically significant only for retail workers (OR 6.8, 95% CI 1.9-24.3) who also reported more fatigue (OR 10.7, 95% CI 2.7-42.7). Container handlers with the highest exposure-duration were more likely to report ≥ 10 symptoms, both when compared with reference workers (OR 4.0, 95% CI 1.4-11.7) and with container handlers with shorter exposure duration (OR 7.5, 95% CI 1.7-32.8). The duration of container handling was particularly associated with symptoms in the memory/concentration domain, again both when compared to reference workers (OR 8.8, 95% CI 2.5-31.4) and workers with the lowest exposure-duration (OR 6.8, 95% CI 1.5-30.3).

CONCLUSION

Container handlers may have an increased risk of neuropsychological symptoms, especially in the memory/concentration domain. Retail workers may also be at risk, but this requires confirmation in a larger study.

Airborne Fumigants and Residual Chemicals in Shipping Containers Arriving in New Zealand

Background

Airborne fumigants and other hazardous chemicals inside unopened shipping containers may pose a risk to workers handling containers.

Methods

Grab air samples from 490 sealed containers arriving in New Zealand were analysed for fumigants and other hazardous chemicals. We also collected grab air samples of 46 containers immediately upon opening and measured the total concentration of volatile organic compounds in real-time during ventilation. Additive Mixture Values (AMV) were calculated using the New Zealand Workplace Exposure standard (WES) and ACGIH Threshold Limit Values (TLV) of the 8-h, time-weighted average (TWA) exposure limit. Regression analyses assessed associations with container characteristics.

Results

Fumigants were detectable in 11.4% of sealed containers, with ethylene oxide detected most frequently (4.7%), followed by methyl bromide (3.5%). Other chemicals, mainly formaldehyde, were detected more frequently (84.7%). Fumigants and other chemicals exceeded the WES/TLV in 6.7%/7.8%, and 7.8%/20.0% of all containers, respectively. Correspondingly, they more frequently exceeded ‘1’ for the AMV-TLV compared to the AMV-WES (25.7% versus 7.8%). In samples taken upon opening of doors, fumigants were detected in both fumigated and non-fumigated containers, but detection frequencies and exceedances of the WES, TLV, and AMVs were generally higher in fumigated containers. Detection frequencies for other chemicals were similar in fumigated and non-fumigated containers, and only formaldehyde exceeded both the WES and TLV in both container groups. Volatile compounds in container air reduced rapidly during ventilation. Some cargo types (tyres; personal hygiene, beauty and medical products; stone and ceramics; metal and glass; and pet food) and countries of origin (China) were associated with elevated airborne chemical and fumigant concentrations.

Conclusion

Airborne chemicals in sealed containers frequently exceed exposure limits, both in fumigated and non-fumigated containers, and may contribute to short-term peak exposures of workers unloading or inspecting containers.

Presumed Exposure to Chemical Pollutants and Experienced Health Impacts among Warehouse Workers at Logistics Companies: A Cross-Sectional Survey

During intercontinental shipping, freight containers and other closed transport devices are applied. These closed spaces can be polluted with various harmful chemicals that may accumulate in poorly ventilated environments. The major pollutants are residues of pesticides used for fumigation as well as volatile organic compounds (VOCs) released from the goods. While handling cargos at logistics companies, workers can be exposed to these pollutants, frequently without adequate occupational health and safety precautions. A cross-sectional questionnaire survey was conducted among potentially exposed warehouse workers and office workers as controls at Hungarian logistics companies (1) to investigate the health effects of chemical pollutants occurring in closed spaces of transportation and storage and (2) to collect information about the knowledge of and attitude toward workplace chemical exposures as well as the occupational health and safety precautions applied. Pre-existing medical conditions did not show any significant difference between the working groups. Numbness or heaviness in the arms and legs (AOR = 3.99; 95% CI = 1.72–9.26) and dry cough (AOR = 2.32; 95% CI = 1.09–4.93) were significantly associated with working in closed environments of transportation and storage, while forgetfulness (AOR = 0.40; 95% CI = 0.18–0.87), sleep disturbances (AOR = 0.36; 95% CI = 0.17–0.78), and tiredness after waking up (AOR = 0.40; 95% CI = 0.20–0.79) were significantly associated with employment in office. Warehouse workers who completed specific workplace health and safety training had more detailed knowledge related to this workplace chemical issue (AOR = 8.18; 95% CI = 3.47–19.27), and they were significantly more likely to use certain preventive measures. Warehouse workers involved in handling cargos at logistics companies may be exposed to different chemical pollutants, and the related health risks remain unknown if the presence of these chemicals is not recognized. Applied occupational health and safety measures at logistics companies are not adequate enough to manage this chemical safety issue, which warrants awareness raising and the introduction of effective preventive strategies to protect workers’ health at logistics companies.

Exposures to Fumigants and Residual Chemicals in Workers Handling Cargo from Shipping Containers and Export Logs in New Zealand

OBJECTIVES

Previous studies have reported high concentrations of airborne fumigants and other chemicals inside unopened shipping containers, but it is unclear whether this is reflective of worker exposures.

METHODS

We collected personal 8-h air samples using a whole-air sampling method. Samples were analysed for 1,2-dibromoethane, chloropicrin, ethylene oxide, hydrogen cyanide, hydrogen phosphide, methyl bromide, 1,2-dichloroethane, C2-alkylbenzenes, acetaldehyde, ammonia, benzene, formaldehyde, methanol, styrene, and toluene. Additive Mixture Values (AMVs) were calculated using the New Zealand Workplace Exposure standard (WES) and American Conference of Governmental Industrial Hygienists (ACGIH) Threshold Limit Values (TLVs) of the 8-h, time-weighted average exposure limit. Linear regression was conducted to assess associations with work characteristics.

RESULTS

We included 133 workers handling shipping containers, 15 retail workers unpacking container goods, 40 workers loading fumigated and non-fumigated export logs, and 5 fumigators. A total of 193 personal 8-h air measurements were collected. Exposures were generally low, with >50% below the limit of detection for most chemicals, and none exceeding the NZ WES, although formaldehyde exceeded the TLV in 26.2% of all measurements. The AMV-TLV threshold of 1 was exceeded in 29.0% of the measurements. Levels and detection frequencies of most chemicals varied little between occupational groups, although exposure to methyl bromide was highest in the fumigators (median 43 ppb) without exceeding the TLV of 1000 ppb. Duration spent inside the container was associated with significantly higher levels of ethylene oxide, C2-alkylbenzenes, and acetaldehyde, but levels were well below the TLV/WES. Exposure levels did not differ between workers handling fumigated and non-fumigated containers.

CONCLUSIONS

Personal exposures of workers handling container cargo in New Zealand were mainly below current exposure standards, with formaldehyde the main contributor to overall exposure. However, as it is not clear whether working conditions of participants included in this study were representative of this industry as a whole, and not all relevant exposures were measured, we cannot exclude the possibility that high exposures may occur in some workers.

Phosphine fumigation - Time dependent changes in the volatile profile of table grapes

Industrial and agricultural goods are fumigated in transport containers in order to control pest infestations and to avoid the transmission of alien species. Phosphine is increasingly used prior to the export as fumigant for table grapes, fruit cultures and dried fruits to control active table grapevine insect pests. Less knowledge exists for fumigants about the desorption time of toxic gases and factors that affect the composition of the fumigated good. Therefore, red and white table grapes (´Thompson seedless´, ´Scarlotta´ and ´Flame seedless´) were chosen to represent the allowed group of phosphine fumigated foods and were treated with a concentration of 2000 vpm phosphine (PH₃) at different temperatures. In the present study, sorption and desorption behavior of PH₃ by table grapes and possible changes in their VOC (volatile organic compounds) profiles were investigated. The PH₃ concentration was monitored before and after the fumigation process and was determined under the maximum residue level 0.005 ppm after 35 days. The adsorbed amount of PH₃ was not influenced by fumigation parameters. For analysis of the influences on the volatile profile after fumigation, a headspace solid-phase micro-extraction coupled to gas chromatography mass spectrometry (HS-SPME-GC/MS) was used. Small differences in volatile profiles of fumigated and subsequently outgassed table grapes compared to non-fumigated table grapes could be observed. A slight influence on the aldehyde group directly after fumigation could be perceived by a decrease of hex-2-en-1-ol and 1- hexanol in PH₃-treated table grapes. The concentrations of both compounds increase again after completion of the desorption process. On the other hand terpenes are not significantly influenced by the fumigation process. Overall these changes are likely to affect table grape aroma characteristics directly after a treatment with PH₃ and it could be demonstrated that phosphine alters the volatile profile of fumigated table grapes qualitatively and quantitatively.

DNA damage and inflammatory response in workers exposed to fuels and paints

Workers exposed to fuels and paints may present alterations in several parameters. Thus, we assessed potential biomarkers, with the aim of detecting early changes in gasoline station attendants and painters. Blood samples were collected for the analysis of inflammatory and DNA damage markers, besides biochemical, haematological and oxidative stress parameters. Biochemical and haematological parameters, which are assessed with routine exams, showed few changes. However, these findings could mask the workers' real health status. Besides, markers of oxidative damage were not modified. Levels of inflammatory parameters (cytokines and nitric oxide levels) and the DNA damage marker 8-hydroxydeoxyguanosine were significantly changed in the workers. Our results suggest that inflammatory and DNA damage parameters can be potential biomarkers for the biological monitoring of workers exposed to fuels and paints and may contribute to the development of occupational protection standards.

Influence of fumigants on sunflower seeds: Characteristics of fumigant desorption and changes in volatile profiles

Fumigation of transport containers is common practice to protect stored products from pests. Yet little is known about the desorption times and effects of the highly toxic gases used in this process. To shed light on the behavior of fumigants in real food, we treated sunflower seeds (Helianthus annuus L.) with 100ppm phosphine (PH₃), methyl bromide (MeBr) or 1,2-dichloroethane (DCE) for 72h. The compound concentrations in the air were then analyzed by thermal desorption/2D gas chromatography coupled to mass spectrometry and flame photometric detection (TD-2D-GC-MS/FPD). A desorption time of several months was observed for DCE, whereas PH₃ and MeBr were outgassed in a matter of days. To investigate possible interactions between gases and constituents of the seeds, non-fumigated, fumigated and outgassed samples were analyzed by headspace solid-phase microextraction GC-MS. We observed significantly different volatile profiles in fumigated and subsequently outgassed seeds compared to non-fumigated seeds. Whereas PH₃-treated seeds released far more terpenoids, the volatile pattern of seeds exposed to DCE revealed significantly fewer terpenoids but more aldehydes. These changes are likely to affect food aroma characteristics.

Experimental outgassing of toxic chemicals to simulate the characteristics of hazards tainting globally shipped products

Ambient monitoring analyses may identify potential new public health hazards such as residual levels of fumigants and industrial chemicals off gassing from products and goods shipped globally. We analyzed container air with gas chromatography coupled to mass spectrometry (TD-2D-GC-MS/FPD) and assessed whether the concentration of the volatiles benzene and 1,2-dichloroethane exceeded recommended exposure limits (REL). Products were taken from transport containers and analyzed for outgassing of volatiles. Furthermore, experimental outgassing was performed on packaging materials and textiles, to simulate the hazards tainting from globally shipped goods. The mean amounts of benzene in analyzed container air were 698-fold higher, and those of ethylene dichloride were 4.5-fold higher than the corresponding REL. More than 90% of all containers struck with toluene residues higher than its REL. For 1,2-dichloroethane 53% of containers, transporting shoes exceeded the REL. In standardized experimental fumigation of various products, outgassing of 1,2-dichloroethane under controlled laboratory conditions took up to several months. Globally produced transported products tainted with toxic industrial chemicals may contribute to the mixture of volatiles in indoor air as they are likely to emit for a long period. These results need to be taken into account for further evaluation of safety standards applying to workers and consumers.

Short-term health effects in the general population following a major train accident with acrylonitrile in Belgium

BACKGROUND

Following a train derailment, several tons of acrylonitrile (ACN) exploded, inflamed and part of the ACN ended up in the sewage system of the village of Wetteren. More than 2000 residents living in the close vicinity of the accident and along the sewage system were evacuated. A human biomonitoring study of the adduct N-2-cyanoethylvaline (CEV) was carried out days 14-21 after the accident.

OBJECTIVES

(1) To describe the short-term health effects that were reported by the evacuated residents following the train accident, and (2) to explore the association between the CEV concentrations, extrapolated at the time of the accident, and the self-reported short-term health effects.

METHODS

Short-term health effects were reported in a questionnaire (n=191). An omnibus test of independence was used to investigate the association between the CEV concentrations and the symptoms. Dose-response relationships were quantified by Generalized Additive Models (GAMs).

RESULTS

The most frequently reported symptoms were local symptoms of irritation. In non-smokers, dose-dependency was observed between the CEV levels and the self-reporting of irritation (p=0.007) and nausea (p=0.007). Almost all non-smokers with CEV concentrations above 100pmol/g globin reported irritation symptoms. Both absence and presence of symptoms was reported by non-smokers with CEV concentrations below the reference value and up to 10 times the reference value. Residents who visited the emergency services reported more symptoms. This trend was seen for the whole range of CEV concentrations, and thus independently of the dose.

DISCUSSION AND CONCLUSION

The present study is one of the first to relate exposure levels to a chemical released during a chemical incident to short-term (self-reported) health effects. A dose-response relation was observed between the CEV concentrations and the reporting of short-term health effects in the non-smokers. Overall, the value of self-reported symptoms to assess exposure showed to be limited. The results of this study confirm that a critical view should be taken when considering self-reported health complaints and that ideally biomarkers are monitored to allow an objective assessment of exposure.

Health risks in international container and bulk cargo transport due to volatile toxic compounds

To ensure the preservation and quality of the goods, physical (i.e. radiation) or chemical pest control is needed. The dark side of such consents may bear health risks in international transport and production sharing. In fact, between 10% and 20% of all containers arriving European harbors were shown to contain volatile toxic substances above the exposure limit values. Possible exposure to these toxic chemicals may occur not only for the applicators but also the receiver by off gassing from products, packing materials or transport units like containers. A number of intoxications, some with lethal outcome, occur not only during the fumigation, but also during freight transport (on bulk carriers and other transport vessels), as well as in the logistic lines during loading and unloading. Risk occupations include dock-workers, seafarers, inspectors, as well as the usually uninformed workers of importing enterprises that unload the products. Bystanders as well as vulnerable consumers may also be at risk. Ongoing studies focus on the release of these toxic volatile substances from various goods. It was shown that the half-lives of the off-gassing process range between minutes and months, depending on the toxic substance, its chemical reactivity, concentration, the temperature, the contaminated matrix (goods and packing materials), and the packing density in the transport units. Regulations on declaration and handling dangerous goods are mostly not followed. It is obvious that this hazardous situation in freight transport urgently requires preventive steps. In order to improve awareness and relevant knowledge there is a need for more comprehensive information on chemical hazards and a broader implementation of the already existing regulations and guidelines, such as those from ILO, IMO, and national authorities. It is also necessary to have regular controls by the authorities on a worldwide scale, which should be followed by sanctions in case of disregarding regulations. Further, fumigated containers must have a warning sign corresponding to international recommendations and national regulations, and freight documents have to indicate any potential hazard during stripping the goods.