Chemical hazards
Chemical hazards in the workplace are a prevalent worry across multiple industries, presenting dangers to employees’ well-being and the work environment’s overall stability. These hazards include contact with various chemical compounds, such as harmful substances, combustible elements, corrosive materials, etc. Over 30 million employees within the United States are subject to unsafe chemicals in their workplace (33). The 2021 data addendum reveals that in 2019, exposure to specific chemicals resulted in the loss of approximately two million lives and 53 million disability-adjusted life-years. Nearly 50% of the deaths linked to chemical exposures that year were primarily caused by lead exposure, leading to cardiovascular diseases (34). Employees can be exposed to chemicals at the workplace through inhalation, eye contact, skin contact, ingestion, and injection (35). Exposure to chemicals at work can have several effects on health, ranging from skin burns, anthrax, aches, ulcers in the hand and nose, irritation of windpipes, and cancer (36).
Hazardous workplace chemicals vary based on the work environment. These pose significant health risks, highlighting the need to understand the different types and potential consequences. These chemical hazards are categorized as toxic, corrosive, irritant, carcinogenic, flammable, and mutagenic (36). Toxic chemicals are commonly present in chemical manufacturing, agriculture, and mining industries, where substances like solvents and pesticides are utilized (37,38). Exposure to these toxins can lead to both acute and chronic health issues, such as respiratory problems, organ damage, and even cancer. Irritants and corrosives, on the other hand, encompass chemicals like strong acids, cleaning agents, and alkalis, which find application in industries like manufacturing, cleaning, and metalworking (36). Carcinogens are used in many industries like healthcare, construction, and laboratories. Some of these carcinogens include asbestos, formaldehyde, and certain solvents. Prolonged exposure to carcinogenic substances poses a serious threat to workers’ health as it can lead to the development of cancer (39). In industries such as chemical plants, oil refineries, and automotive repair shops, the use of flammable and combustible chemicals like gasoline, aerosols, and propane increases the risk of exposure, potentially resulting in burns, asphyxiation, or even fatalities (40).
Mutagenic substances encountered in workplaces can cause DNA changes and genetic mutations in exposed individuals, significantly elevating the risk of enduring health issues, including a variety of cancers. Exposure to these mutagenic substances in the workplace can have long-lasting and profound health consequences, with the substances encompassing a wide array of chemicals, ranging from specific solvents and heavy metals to pharmaceuticals and even ionizing radiation, such as X-rays and gamma rays (40,41).
Several studies have been conducted to determine the effect of chemical exposure on individuals in the workplace. In research conducted by Herman Gibb and fellow researchers, the objective was to assess the lung cancer risk associated with exposure to both trivalent and hexavalent chromium among individuals employed in chromium production facilities. They examined a cohort comprising 2,357 workers who were initially hired between 1950 and 1974 at a chromate production plant, and the vital status of these workers was tracked until December 31, 1992. From examining the cohort, a progressive relationship between cumulative hexavalent exposure and the incidence of lung cancer was indicated (39). According to Van Rooy et al (42), the development of bronchiolitis obliterans syndrome among chemical process operators was attributed to their exposure to diacetyl during its manufacturing for food flavorings (42). Armando Meyer and his team conducted a study examining the correlation between the risk of rheumatoid arthritis and the utilization of pesticides among male pesticide applicators enrolled between 1993 and 1997. The study found that heightened occurrences of rheumatoid arthritis were linked to exposure to various pesticides, including fonofos, carbaryl, and imuran ethyl (38). In a similar study, Parks et al (43) observed an elevated risk of rheumatoid arthritis and the associated condition, systemic lupus erythematosus, in women who self-reported using insecticides during the Women’s Health Initiative Observational Study. This risk was more pronounced in women with a farming background. In a sample of the US population as part of the National Health and Nutrition Examination Survey, increased serum levels of organochlorine insecticides were linked to self-reported cases of arthritis, including rheumatoid arthritis (43).
Long-term pesticide exposure was linked to increased abnormalities in nerve conduction, particularly in sensory nerves. This extended exposure also broadly impacted various health indicators based on blood tests. It resulted in reduced amplitudes of the tibial nerve’s compound muscle action potential. Short-term exposure had immediate health effects, including changes in complete blood count, hepatic and renal functions, and alterations in nerve conduction velocities and amplitudes (44).
The exposure to chemical hazards originating from coal combustion emissions and diesel engine exhaust was determined to be correlated with urinary mutagenicity, which in turn was associated with an increased risk and development of cancer at multiple locations in the body (40). Therefore, reducing employees’ exposure to chemical hazards within their workplace is crucial. Emerging chemical hazards in various industries arise from new chemical compounds, processes, and evolving risk awareness. They can result from innovative chemicals, processes, or the discovery of previously unrecognized risks in existing substances. It is crucially important to adopt a forward-looking strategy to anticipate potential risks posed by chemicals to the health and safety of workers within an ever-evolving work landscape.
With the constant changes in work, an imminent requirement exists to proactively identify potential hazards that may not yet be known or expected. Early detection and alerts can significantly mitigate the likelihood of severe consequences in terms of negative health impacts and broader socio-economic ramifications. Some of the emerging chemicals include nanomaterials, per- and polyfluoroalkyl substances (PFAS), and metal-organic frameworks (MOFs). In recent years, there has been a growing interest in the use of nanotechnology. Nanotechnology involves manipulating matter at scales below 100 nm, resulting in nanoparticles with high surface area-to-volume ratios that enhance reactivity and affect chemical reaction rates (45). Nanomaterials, owing to their unique and beneficial characteristics encompassing chemical reactivity (due to their small size), ductility, flexibility, optical properties, biocompatibility, tunability, enhanced strength, and improved magnetic attributes, offer versatile applications across an array of industries. These applications span diverse fields, including electronics, medicine, energy, aerospace, food production, textiles, cosmetics, and construction (46). PFAS, or per- and polyfluoroalkyl substances, represent a group of artificially produced chemicals. Typically, they contain a carbon chain with most carbon sites saturated by fluorine atoms, along with at least one functional group, like carboxylic acid, sulfonic acid, or amine.
It is important to note that the carbon backbone may not be exclusively carbon; for instance, ether-type PFAS include oxygen atoms in their structure (47). Due to their high production costs, PFAS are typically employed in scenarios where alternative substances are unable to meet the necessary performance standards, or where PFAS can function effectively in much smaller quantities compared to non-fluorinated chemicals while delivering the same level of performance. For instance, they are utilized in applications that operate across broad temperature ranges and in situations that demand exceptionally stable and non-reactive materials (48). PFAS have gained widespread usage across more than 200 application areas, ranging from industrial-mining operations to food production and fire-fighting foams. The key driving force behind the extensive adoption of PFAS lies in the remarkable properties associated with the carbon-fluorine (C-F) bond, which imparts exceptional chemical and thermal stability and the unique ability to repel oil and water (48). MOFs are ordered crystalline materials characterized by structured networks. These frameworks are composed of single metal ions or clusters linked together by multidentate organic groups (49). Their distinct characteristics, such as their expansive surface area, adjustable porosity, and varied chemical compositions, render them applicable across various fields (49). These fields include gas storage and purification, catalysis, drug delivery, energy storage, electronics, coating and films, photocatalysis, and hydrogen storage (49, 50).