“Breath,” the simple act we perform countless times a day, without a second thought, can set in motion a process that goes beyond the act of inhalation if it carries an unseen accomplice – Volatile Organic Compound (VOC). VOC is an often overlooked hazard that infiltrates the air and can have profound consequences on our health and the environment. Every year, 3.2 million people die prematurely from household air pollution, according to the World Health Organization (WHO). VOCs—organic chemical compounds found in various products that easily vaporize—are one of the leading constituents of household air.
In this blog, we delve into the hidden dangers lingering in the air we breathe, exploring the pervasive presence of VOCs and their profound impact on our health and the environment.
What are VOCs?
VOCs are a group of organic chemicals that readily evaporate into the air when exposed to room temperature. They are called “volatile” because of their tendency to vaporize and enter the air. They represent a category of airborne chemicals released from various liquids and solids. These compounds pose health risks, with some causing immediate discomfort and others leading to persistent health issues. Indoor environments can harbor concentrations of VOCs up to ten times greater than those found outdoors, amplifying the potential health hazards. Numerous readily available products on the market contribute to this concerning scenario by emitting these harmful compounds.
What are Some Common Sources of VOCs?
VOCs originate from diverse sources; some of the common sources are as follows:
The utilization and burning of fossil fuels stand out as a primary contributor, as incomplete combustion and evaporation processes release VOCs into the atmosphere.
Another significant source is the solvents in paints and inks. Globally, approximately 12 billion liters of paint are produced annually, containing solvents like aliphatic hydrocarbons, ethyl acetate, glycol ethers, and acetone.
Compressed aerosols, primarily those containing butane and propane, contribute substantially to the global VOC emissions, amounting to a staggering 1.3 billion tonnes annually.
The adoption of biofuels, including cooking oils, bioethanol, and other bio-based fuels, is another avenue for VOC release.
Biomass combustion, particularly from forests and agricultural residues, releases VOCs when incomplete combustion occurs.
Metalworking fluids (MWFs) and the incineration of household wastes further add to the list of sources.
Classification and Health Effects of VOCs
Organic contaminants, categorized based on their volatility, fall into three distinct groups:
VVOCs: The category of Very Volatile Organic Compounds (VVOCs) stands out as the most hazardous group of pollutants, as they exhibit toxicity at extremely low concentrations. This classification includes substances such as propane, butane, and methyl chloride. Propane, for instance, transported as a liquefied gas under its vapor pressure and commonly employed for heating or cooking purposes, poses a high level of danger. Similarly, butane, utilized in a manner akin to propane, is recognized as one of the more harmful volatile compounds to inhale.
VOCs: VOCs, as hazardous as VVOCs, are found in common household items and can exist in the surrounding environment. This category includes substances like formaldehyde, vinyl chloride, carbon tetrachloride, toluene, acetone, isopropyl alcohol, hexanal, carbon disulfide, and others. Formaldehyde is often present in adhesives, molded plastics, coatings, insulating substances, and manufactured wood items like plywood, particleboard, and laminate flooring. Vinyl chloride is used in the production of plastics (PVC), floor coverings, and consumer products. It is considered to have a significant likelihood of causing cancer. Carbon tetrachloride is an organic compound employed in fire extinguishers, as a precursor to refrigerants, and as a cleaning agent. Exposure to elevated concentrations of carbon tetrachloride, particularly in vapor form, may adversely impact the central nervous system and lead to the degeneration of the liver and kidneys. Prolonged exposure can potentially result in fatality.
SVOCs: Semi-volatile organic compounds (SVOCs), distinguished by their higher molecular weight and boiling point compared to VOCs, are less likely to vaporize at room temperature. However, this does not diminish their potential danger to people and the environment. SVOCs are present as additives in building materials, furnishings, electronics, and furniture and can lead to significant issues due to their toxicity. Examples of SVOCs include pesticides, chlordane, and benzyl alcohol. Pesticides, particularly organochlorine pesticides, find extensive use in agriculture, causing severe health and environmental problems as neurotoxicants. Benzyl alcohol, used as a solvent, preservative, fragrance, and cosmetic ingredient, is also used in inks, photographic development, and the dyeing process for nylon filament, textiles, and sheet plastics. Exposure to elevated concentrations of benzyl alcohol may result in toxic effects such as respiratory failure, vasodilation, hypotension, convulsions, and paralysis.
Many products we use daily expose us to VOCs, often without our awareness of their potential health effects. VOC exposure can lead to various adverse health conditions, including cancer in both humans and animals, severe headaches, nausea, and damage to the central nervous system, liver, and kidneys. Symptoms such as dizziness, fatigue, conjunctival irritation, vomiting, allergic skin reactions, nosebleeds, breathing difficulty, and discomfort in the throat and nose may indicate exposure. Additionally, a gradual decline in serum cholinesterase levels is observed. The severity of health effects depends on the toxicity level of the organic chemicals and the duration of exposure. Immediate symptoms from high levels of exposure include dizziness, respiratory and eye discomfort, memory impairment, visual disturbance, and headaches. Recognizing these signs is crucial for mitigating potential health risks associated with VOC exposure.
VOC Monitoring Methods
Effective monitoring of VOC levels is crucial to prevent potential damage to internal organs from prolonged exposure and to address long-term health issues associated with low-level exposure. Two widely employed methods for VOC monitoring are:
Flame Ionization Detection (FID)
Photo Ionization Detection (PID)
Flame ionization detectors use a hydrogen flame to ionize VOCs, but they may be cumbersome due to the need for a hydrogen cylinder for gas supply. To ensure accurate readings, a heated sample line is recommended during VOC extraction to prevent condensation. Photo ionization detectors, similar to flame ionization detectors, ionize VOCs but use ultraviolet light instead. An advantageous feature of photo ionization detectors is their ability to eliminate Methane while measuring VOCs, allowing for accurate readings by disregarding background levels of methane in the atmosphere.
Most continuous VOC monitoring devices in the market use the PID technique for measuring the concentration of diverse VOC compounds. PID enables sensors to detect VOCs even at low concentrations.
Here’s how PID works:
A photo ionization detector has an ultraviolet lamp that emits photons. When the compound absorbs these photons, it prompts the release of electrons, resulting in the creation of positive ions. These ions are collected on electrodes, and the ensuing current provides a precise measure of the compound’s concentration. The advantages of PID technology include cost-effectiveness, user-friendly operation, real-time measurement capabilities, and the ability to detect very low concentrations.
What is the Role of Environmental Testing Laboratories?
Environmental testing laboratories play a vital role in safeguarding environmental and public health. They monitor air, water, and soil samples to assess environmental contamination levels and enforce pollution control measures. They also evaluate indoor air quality, ensuring safe environments in workplaces and homes. By analyzing consumer products for VOC content, these labs contribute to product safety and regulatory compliance. These laboratories assess health risks associated with specific compounds, supporting health impact assessments and regulatory decision-making. Through research and development efforts, they advance our understanding of VOC behavior, sources, and effects, contributing to the development of improved testing methods and environmental policies for a sustainable future.
The Role of Environmental LIMS Software in Accurately Testing VOCs
Environmental laboratories specializing in VOC identification and testing often handle numerous samples simultaneously. Environmental LIMS software allows for easy tracking of samples throughout the testing process, ensuring traceability from sample receipt to analysis. Apart from ensuring accurate sample tracking and traceability, environmental LIMS software aids in efficient data management and automates workflows, reducing manual tasks and minimizing the risk of errors. This is particularly important in VOC testing, where accuracy is paramount. Automated workflows help maintain consistency and reliability in testing procedures. Furthermore, environmental LIMS software enables laboratories to avoid regulatory pitfalls and meet the reporting requirements of clients and regulatory authorities.
The pervasive presence of VOCs in our homes and the environment poses significant health and environmental risks, contributing to millions of premature deaths annually. Common sources, such as fossil fuel use, paints, aerosols, biofuels, and biomass combustion, release a variety of VOCs, including hazardous VVOCs, VOCs, and SVOCs. These compounds, found in everyday products, can lead to severe health effects, emphasizing the importance of recognizing and mitigating exposure. Environmental laboratories play an important role in this process, identifying and quantifying VOCs to safeguard environmental and public health. Monitoring methods, particularly those utilizing the PID technique, enable the detection of VOCs even at low concentrations. In this crucial work, environmental LIMS software systems prove invaluable, ensuring accurate sample tracking, efficient data management, and streamlined workflows. As we breathe in a world laden with VOCs, monitoring and testing are paramount for a healthier and more sustainable future.