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

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.

Recent developments and applications of selected ion flow tube mass spectrometry (SIFT-MS)

Selected ion flow tube mass spectrometry (SIFT-MS) is now recognized as the most versatile analytical technique for the identification and quantification of trace gases down to the parts-per-trillion by volume, pptv, range. This statement is supported by the wide reach of its applications, from real-time analysis, obviating sample collection of very humid exhaled breath, to its adoption in industrial scenarios for air quality monitoring. This review touches on the recent extensions to the underpinning ion chemistry kinetics library and the alternative challenge of using nitrogen carrier gas instead of helium. The addition of reagent anions in the Voice200 series of SIFT-MS instruments has enhanced the analytical capability, thus allowing analyses of volatile trace compounds in humid air that cannot be analyzed using reagent cations alone, as clarified by outlining the anion chemistry involved. Case studies are reviewed of breath analysis and bacterial culture volatile organic compound (VOC), emissions, environmental applications such as air, water, and soil analysis, workplace safety such as transport container fumigants, airborne contamination in semiconductor fabrication, food flavor and spoilage, drugs contamination and VOC emissions from packaging to demonstrate the stated qualities and uniqueness of the new generation SIFT-MS instrumentation. Finally, some advancements that can be made to improve the analytical capability and reach of SIFT-MS are mentioned.

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.

A novel method for pre-ventilation of shipping containers

Numerous shipping containers arrive with high levels of hazardous volatile chemicals in the interior air. This may constitute a health risk during inspection and unstuffing. The problem remains largely unaddressed due to ignorance, lack of suitable field instruments for chemical identification, and lack of easy to use, effective ventilation methods. Here, we present a novel ventilation approach based on extraction of air from the closed container via the existing top corner ventilators. A suction plate was developed to fit tightly over the corner ventilator and connected with a flexible hose to an extraction fan. Air flow rates and vacuum under the plate were measured in the lab with five different types of extraction fans. The vacuum produced under the suction plate held it securely in place. Washout of air contaminants under different configurations and ventilation scenarios was studied in an experimental 20-ft container stuffed with acetone emitting cardboard boxes and in the field with containers stuffed with commercial goods. Volatiles in container air were continuously recorded with logging photoionization detectors in various positions before, during and after ventilation. A maximum air flow through the ventilator of 186 m³/h was achieved. At 100 m³/h, the initial acetone levels were reduced to 11% and 4.9% in the tightly stuffed and to 6.0% and 3.1% in the loosely stuffed (pallets) experimental container after 1 h and 4 h, respectively, as measured inside the closed door (mean values). As expected, the washout was somewhat slower in nine 40-ft field containers and reached 22% and 11%, respectively. In both experimental and field containers the concentration rose quickly when ventilation ceased. In conclusion, the new ventilation method allows for convenient, safe and efficient ventilation of risk containers. The container should be continuously ventilated until it is opened, or rapid re-accumulation of volatiles will occur.