Occupational Exposure Monitoring in a Cutting-Edge Recycling Facility: A Comprehensive Case Study

This compelling case study highlights our expertise in occupational exposure monitoring within a state-of-the-art recycling facility. As a leading provider of innovative and sustainable waste management solutions, our client operates a wide range of processes for sorting, treating, and recycling diverse classifications of waste. We were entrusted with the critical task of assessing and managing the occupational health risks associated with dust and volatile fumes generated during these operations.

Our comprehensive approach involved monitoring and evaluating exposure to various types of dust, including generic dust commonly found in recycling environments, microbiological dust, and plastic dust. Additionally, we focused on volatile fumes emitted during the recycling of lithium-ion batteries, known for their potential hazards.

By deploying advanced monitoring techniques and state-of-the-art equipment, we gathered accurate data on airborne contaminants and their concentrations. Our team of experts analysed the results in accordance with relevant occupational exposure limits and guidelines, ensuring a thorough assessment of potential health risks.

Based on our findings, we formulated tailored control measures and risk management strategies to minimize worker exposure. These encompassed the implementation of engineering controls, such as local exhaust ventilation systems, and the provision of personal protective equipment designed to mitigate inhalation risks and safeguard workers' health.

Through our expertise and commitment to worker safety, we empowered the recycling facility to proactively protect their employees and ensure compliance with occupational health standards. Our recommendations and strategies provided valuable insights into optimizing work practices, refining ventilation systems, and enhancing overall safety culture within the facility.

Risks encountered

 
Microbiological exposure poses a significant risk to workers in recycling facilities, particularly during the handling and sorting of waste materials. As these facilities process diverse classifications of waste, including organic and biodegradable materials, they provide an ideal environment for the growth and proliferation of various microorganisms. When workers come into contact with contaminated waste materials, they face the potential exposure to harmful bacteria, viruses, fungi, and other microorganisms. These microorganisms can be present in various forms, such as aerosols, bioaerosols, or biohazardous residues on surfaces.

Exposure to microbiological hazards can occur through inhalation of airborne particles, direct contact with contaminated surfaces, or even accidental ingestion. Workers involved in sorting, processing, or handling waste materials are at an increased risk of exposure, especially if proper preventive measures are not in place.
 
Plastic dust generated during the plastic shredding process poses significant health risks to workers in recycling facilities. Plastic materials, when subjected to shredding, grinding, or other mechanical processes, can release fine particulate matter into the air, leading to the formation of plastic dust. This dust contains a mixture of plastic particles, additives, and potentially hazardous chemicals, which can be inhaled or come into contact with the skin during work activities.

The inhalation of plastic dust can result in respiratory health issues. Fine plastic particles can penetrate deep into the respiratory system, reaching the lungs and causing irritation, inflammation, and respiratory distress. Prolonged exposure to plastic dust may contribute to the development of chronic respiratory conditions such as asthma, bronchitis, or even more severe respiratory diseases. In addition to respiratory risks, plastic dust can also pose a threat to the skin and eyes. Direct contact with plastic dust particles may lead to skin irritation, dryness, or allergic reactions. If the dust comes into contact with the eyes, it can cause irritation, redness, and potential damage to the delicate eye tissues.

Furthermore, the composition of plastic dust can vary depending on the types of plastic materials being shredded. Certain plastics may contain additives or chemicals that can be hazardous to human health, such as flame retardants, plasticizers, or heavy metals. These substances can pose long-term health risks if workers are exposed to them repeatedly or in high concentrations.

Volatile components of lithium-ion batteries such as Diethyl carbonate and fluorobenzene serve various purposes within the battery, but they also present potential health risks when released into the environment, particularly during the recycling process.

Diethyl carbonate is a solvent that helps dissolve lithium salts and facilitate the movement of ions within the battery. It is highly flammable and can easily evaporate into the air. Inhalation of diethyl carbonate vapor can irritate the respiratory system and may cause symptoms such as coughing, shortness of breath, and chest discomfort. Prolonged or repeated exposure to diethyl carbonate may also lead to more severe respiratory issues and can have adverse effects on the liver and kidneys.

Fluorobenzene, on the other hand, is used as a solvent and electrolyte additive in lithium-ion batteries. It is a volatile organic compound with a low boiling point, which means it can vaporise at room temperature and create potentially hazardous airborne concentrations. Inhalation of fluorobenzene vapor can irritate the respiratory system and cause dizziness, headaches, and nausea. Long-term exposure to high levels of fluorobenzene may lead to more serious health effects, including damage to the central nervous system, liver, and kidneys.

Both diethyl carbonate and fluorobenzene pose risks not only to workers directly involved in battery recycling but also to individuals in the surrounding environment if proper control measures are not in place. These risks are exacerbated during activities such as shredding or disassembling lithium-ion batteries, which can release volatile components into the air as fine aerosols or vapours.

Our method

We employed various methods to assess occupational exposure in the recycling facility, including both microbiological sampling and the monitoring of specific contaminants. For microbiological sampling, we utilised the MAS-100 biosampler in combination with tryptone soy and malt extract agar plates. This method allowed us to collect air samples and evaluate the presence of microbiological contaminants, providing valuable insights into the potential risks associated with microbial exposure in the facility.

In addition to microbiological sampling, we conducted sampling for inhalable dust, volatile organic compounds (VOCs), and metals. Inhalable dust was collected using glass fiber filters (GFA) within IOM cassettes, following the guidelines outlined in MDHS 14/4. This gravimetric method enabled us to measure the mass of inhalable dust particles in the air, giving us an understanding of the overall dust exposure levels.

For the assessment of VOCs, we utilized solid sorbent charcoal tubes (226-01) in accordance with MDHS 104. These tubes effectively trapped and collected VOCs present in the air samples. The collected samples were then analyzed using gas chromatography mass spectrometry (GC-MS), allowing us to identify and quantify the specific VOCs present in the facility.
 
To evaluate the presence of metals, we employed mixed cellulose ester (MCE) filters within IOM cassettes. These filters captured particulate matter containing metals, and the samples were analyzed using inductively coupled plasma optical emission spectrometry (ICP-OES). This method provided us with accurate measurements of metal concentrations in the air, enabling us to assess the potential risks associated with metal exposure in the recycling facility.

By utilizing these comprehensive sampling and analytical techniques, we were able to gather reliable data on microbiological contaminants, inhalable dust, VOCs, and metals in the recycling facility. These findings provided valuable insights into the occupational exposure levels and enabled us to identify potential health risks to workers.
 
 

Our conclusions from the occupational exposure monitoring conducted at the recycling facility are as follows:

The initial measurements indicate a high potential for exceeding the occupational exposure limit if dust control measures are not implemented. Therefore, it is strongly recommended to implement engineering dust control measures to minimize dust levels as much as possible.

During the shredding operations, the main hazards identified are total dust and metallic components in the dust. Some of these metallic components are recognized as carcinogens and sensitizers, requiring the implementation of a formal health surveillance program for the operatives. Respiratory protective equipment should also be provided for tasks involving these hazards.

On a positive note, the results from the second set of measurements show that the mist suppression system effectively reduces the concentration of airborne dust around the shredder. This helps in controlling the exposure to hazardous dusts and vapours below the workplace exposure limits.

Operatives working in close proximity to the shredding machine may experience exposure, although it is unlikely to exceed the workplace exposure limits. Activities such as maintenance, machine clean downs, waste/product handling, and working with the ventilation system require the use of respiratory protection. For routine operation of the shredding machine in the workshop, respiratory protective equipment is not necessary, as the existing control measures are effective in managing dust and vapor emissions.

Some of the volatile components in the fumes released during the process have strong characteristic odours and can be irritating. Although workplace exposure limits have not been assigned to these compounds, it is strongly recommended to minimize their concentration as much as possible.
 
Our findings regarding microbiological exposures in the recycling facility revealed elevated levels of viable bacteria and moulds collected on the agar plates. This is a common occurrence in the indoor air of recycling facilities due to the nature of the materials being processed. Additionally, spore trap samples were collected, which helped identify high levels of fast-growing Penicillium, Aspergillus, and Cladosporium moulds. These moulds pose potential health risks, as exposure to their spores can lead to respiratory issues, allergies, and asthma symptoms in susceptible individuals. It is important for the facility to implement proper ventilation, hygiene practices, and regular cleaning protocols to minimize the risk of microbiological contamination and ensure a safe working environment for the employees.

Value Delivered

By effectively addressing and managing multiple exposure hazards in the recycling facility, we have delivered significant value to our client. Our comprehensive occupational exposure monitoring allowed us to identify and quantify the risks associated with various contaminants, including dust, volatile organic compounds, and microbiological agents. Through our expertise in sampling and analysis methods, we provided accurate data on the levels of these hazards, enabling the client to assess their potential health effects on workers. Additionally, our in-depth knowledge of legislative guidelines and industry best practices allowed us to make practical recommendations for implementing control measures and improving occupational hygiene practices. By mitigating these exposure hazards, we have helped the client create a safer and healthier work environment, protecting the well-being of their employees and ensuring compliance with relevant regulations. Our commitment to delivering valuable insights and actionable recommendations demonstrates our competence and dedication in addressing complex exposure challenges in recycling facilities.
In the rapidly evolving field of lithium-ion battery recycling, where processes are still being established and supported by limited years of experience, we have played a crucial role in helping our client improve the management of health and safety. As a relatively new industry, the potential health risks associated with the handling and processing of lithium-ion batteries were not well understood. However, our expertise in occupational exposure monitoring and our thorough understanding of the potential hazards allowed us to assess the unique risks involved in this field.

By conducting comprehensive exposure monitoring, we were able to gather essential data on the volatile components released during the recycling process. Our findings highlighted the presence of volatile organic compounds (VOCs) and the potential respiratory and irritant effects they can have on workers. Through our recommendations and guidance, we assisted the client in implementing effective engineering controls, such as mist suppression systems, to significantly reduce the concentration of airborne dust and VOCs in the working environment.

Furthermore, our involvement in establishing a formal health surveillance program for operatives working in close proximity to the shredding machine was instrumental in protecting their long-term health. By engaging occupational health monitoring providers and conducting regular health checks, including lung capacity testing, dermatological examinations, audiometry, and vibration damage checks, we ensured early detection of any potential health issues arising from exposure to hazardous substances.
 
Our expertise and proactive approach have been invaluable in supporting our client's efforts to stay ahead of the curve in terms of health and safety management in this emerging field. By leveraging our knowledge of best practices, industry guidelines, and the latest scientific research, we have provided the client with the tools and insights necessary to navigate the unique challenges posed by lithium-ion battery recycling. Through our collaboration, we have not only enhanced the safety of their operations but also positioned them as leaders in promoting the well-being of their workforce in this evolving industry.