Mar 28, 2016
The rundown on volatile organic compounds
By Linda Johnson
Akram Karam worked at Palmone Shoes in Melbourne, Australia, for four years when he developed asthma. Over the course of his employment, he was exposed to a number of different solvents and glues, including benzene. While the employer had conducted air quality testing and said Karam was only ever exposed at or below the acceptable exposure limit, the court found the chemicals lead to Karam’s asthma. In May 2015, Palmone Shoes was ordered to pay $244,000 to the employee.
Benzene is one of a family of chemicals known as volatile organic compounds (VOCs.) These chemicals exist in many building products and, when they evaporate, they contaminate indoor air and cause serious health problems in people who work in offices, stores, schools and vehicles. While VOCs emit an odour, the source of the chemical is often hard to find and can be difficult and costly to remedy.
VOCs, which include acetone, benzene, formaldehyde, methylene chloride, perchloroethylene and toluene, generally dissipate over time by off-gassing. Semi-volatile organic compounds (SVOCs) are less volatile than VOCs and include the phthalates (present in PVC flooring and building materials) and some flame retardants (in furniture). SVOCs release from sources more slowly than VOCs, and their smell can last many years indoors.
Thousands of products emit VOCs. Some common ones are fresh paint, lacquers, glues, flooring adhesives, building materials (caulking and sealants), cleaning supplies, paint strippers, pesticides, preservatives, printers, permanent markers and new carpeting and furniture. They are present in gasoline and other fuels and can be produced by industrial processes (oil refining, solvent release, painting and industrial combustion) and gasoline evaporation.
VOCs can have short- and long-term adverse health effects, including headaches, dizziness, skin irritations or rashes, breathing difficulty, memory impairment and organ damage. Some, such as benzene and 1,3-butadiene, can cause cancer.
The health effects of VOCs are specific to the chemical and vary according to exposure, says Barbara MacKinnon, president and CEO of the New Brunswick Lung Association in Fredericton. Low doses may irritate the nose, throat or eyes. Increased exposures of some VOCs could cause nausea or loss of concentration, while increased exposures of others can cause kidney or liver damage, central nervous damage and cancer.
“So that continuum — from irritation to nausea to organ damage to cancer and subsequently death — depends on which VOC you’re talking about, the level of exposure or concentration of the chemical and the duration that you’re exposed to it,” she says.
Moreover, people react differently to VOCs, she adds. People with existing illnesses, such as asthma, or who have multiple chemical sensitivities will notice effects before a healthy, non-sensitive adult.
Employers and workers often don’t know their building contains harmful levels of VOCs until people start feeling sick, says Silvana Wu, senior project manager at Alberta Safety and Environmental Services in Calgary.
“When only one person is not feeling well, we send them to their doctor first. Normally, if there is an issue with VOCs, there’ll be a lot of people who feel ill: everyone has constant headaches and they feel it only when they’re at work. You tend to get a trend,” she says.
Once an employer or building owner suspects the problem may be environmental, a call is usually made to a consulting firm that tests the air quality. A traditional method involves using a sorbent tubing cassette. A calibrated pump draws air into a sorbent tube and the compounds collect on the absorbent (often activated charcoal) inside the tube. The sample can then be sent to a lab where the concentration of compounds in the air is analyzed.
Another method is to collect a sample of “whole” air in a canister left on-site often for 24 to 48 hours, Wu says. At the lab, the sample is scanned and the types of VOCs present are identified.
A more recently developed technology is the direct-reading monitor. The handheld device has a probe and gives an immediate reading of the total concentration of VOCs but cannot identify exactly which chemicals are present.
If an organization has an air quality problem, MacKinnon says, it should first conduct a “common sense” analysis of the office. Ask: Where do we think the smell is coming from? Do we have vehicles idling outside our windows? Are we using noxious cleaning products? Is our ventilation system working properly?
“If you think you know what it is, remove the source of the VOCs. You can solve a lot of typical office exposures by doing that. If you’ve just painted your office, open windows; don’t let your staff come in until the smell settles down. Very sensitive people might have continuing sensitivities to paint or new flooring a year after, so then it’s a staffing issue: do you want to let that person work from home? Then, if you still can’t nail it down, you can hire a company to come and do a VOC analysis,” she says.
Generally, when VOCs are detected, Wu says, they recommend “flushing out” the building: running the ventilation system with 100 per cent fresh air. It’s important to exchange the air containing VOCs with outdoor air rather than re-circulate it because that air only passes through a filter in the HVAC system, which filters out particulate but usually not VOCs.
“VOCs are just tiny molecules in the air, so they go right through the filter and back into your air,” she says. “You want the contaminated air to get out of the building as quickly as possible. And, as the VOCs off-gas from the product, they will eventually go away.”
In most cases, Wu says, the best way to eliminate VOCs will depend on what their source is. But the remedy will also depend on cost. Solutions can be expensive and it isn’t always possible to say, “Get rid of everything and replace it.”
Sometimes, removing the source is straightforward — a matter of taking out air fresheners or changing products, such as paints or cleaners. Engineering controls may be an option; for example, replacing or modifying the ventilation system. Or, the company could try such administrative controls as putting up a sign banning perfumes or other products.
“There are many different things we can suggest, and it will depend on what’s going on and the levels we’re dealing with,” says Wu.
Bruce Fraser, section head, exposure assessment at Health Canada in Ottawa, recommends companies have a formal complaint-tracking process.
“If there’s a complaint and someone wants to do an indoor air quality investigation, the first question of the investigator should be, ‘Have there been any other complaints?’” he says. “And if you have a log, you may notice that on the third floor, on the northwest corner, there were five complaints and nowhere else. Then you can focus on the area where there are symptoms.”
While workers in chemical plants are protected by detailed regulations for VOCs that company owners must follow, people working in offices or any non-industrial workplaces have guidelines only.
“When an employee complains, ‘I have a headache,’ the employer’s only duty is to make sure they’re protecting the health and safety of their employees. That’s the umbrella clause it falls under. There is no ‘You have to do this’ because VOCs are not an occupational hazard when you work in an office,” says Wu.
However, the American Conference of Governmental Industrial Hygienists sets threshold limit values for occupational exposure.
“There are two different exposure levels: one’s a comfort level; one’s a toxicity level,” MacKinnon says. “Regulations are generally set at a toxicity level, whereas standards are set at a comfort level. Things that are deemed safe from a toxicity level may not be safe for sensitive groups or may not be comfortable for healthy people.”
To further keep workers healthy, Health Canada has published a set of guidelines, including a document called Indoor Air Quality in Office Buildings: A Technical Guide. Moreover, Fraser says, Health Canada and the Canadian Standards Association (CSA) have been working on a product emission standard for formaldehyde in composite wood products. The standard is expected to be published later this year.
In recent years, there have been significant efforts to reduce VOC emissions in buildings. Governments have passed regulations requiring manufacturers to reduce the VOC chemical content of, for example, paint and solvent products.
The availability of low-emission products has made a huge difference in reducing VOC health issues, Fraser says. But these products are not used as much as they could be because they can be more expensive or, perhaps, contractors simply aren’t aware of them. Wider use of low-emission products probably won’t happen until a requirement to do so is included in project bids or in the Safe Building Code.
“That will be when we start to see more change in workplaces,” he says. “So, overall it’s better, but there’s still work to do.”
Linda Johnson is a freelance writer based in Toronto. She can be reached at
This article originally appeared in the
edition of COS.