by David Gecic, 03-17-2019
The EPA published substantial new rules concerning the use of methylene chloride on Friday, March 19, 2019. They banned the consumer use of this product.
Under the 2016 Frank R. Lautenberg Chemical Safety Act for the 21st Century, the EPA chose 10 chemicals for a critical review. Among these were methylene chloride. Methylene chloride is a traditional paint stripping ingredient used for over half a century.
The US used 264 million pounds of methylene chloride in 2015.
The new rules effectively ban its use in any over the counter paint strippers available to the public. Although the EPA banned its use in consumer products it is still allowed in commercial and industrial applications. This is the final EPA ruling on its consumer use only. They may further restrict industrial applications in the future. However, these may be requirements for training, equipment, or some specific use applications. They still could ban it from use but that is less likely than it was a few months ago.
Methylene Chloride
Methylene chloride, also known as dichloromethane, is a highly volatile solvent and a very effective paint stripper. It has serious health concerns but has been used for many years and is still used in the paint and powder coating industry. Although it is hard to compare exact evaporation rates from chemical to chemical, it is in the neighborhood of 90 times as volatile as water.
It penetrates the surface of paint and removes it from the surface. It is also commonly used for bathtub refinishing and graffiti removal.
The EPA estimates paint removal chemicals expose 1.3 million consumers and bystanders each year to methylene chloride.
They determined that consumer use presents an “unreasonable” risk.
Health Problems
Acute exposure to this product can cause death due to asphyxiation. Acute exposure causes dizziness, incapacitation, loss of consciousness, coma and death. Its effects are similar to those of carbon monoxide.
Methylene chloride is a potentially lethal neurotoxin. One of its target organs is the brain and it can kill brain cells. It has anesthetic effects causing metal confusion, lightheadedness, nausea, vomiting, and loss of consciousness. It also affects the rest of the nervous system, liver, respiratory system, kidney and reproductive system.
When methylene chloride contacts water it can breakdown into methanol and hydrochloric acid. This is what causes a burning sensation on wet skin exposed to the fumes of this product. This burns and corrodes tissues. When breathed, it can create acid in the lungs and cause long-term damage.
Cardiotoxic effects have been seen on the electrocardiograms of people exposed to methylene chloride.
It is classified as a likely human carcinogen. There is some human evidence of this material causing bile cancer and brain cancer. There is laboratory evidence of it causing cancer in rats and mice. Strangely, there is no carcinogenic effects found in studies on hamsters.
When the EPA considered the health problems of methylene chloride, they also considered the inhalation hazards to children in the home and other bystanders.
Low exposure limits
OSHA limits are 25 ppm for an eight-hour time-weighted average (TWA) and a Short-Term Exposure Limit (STEL) of 125 ppm. These numbers are meaningless to most people, especially for analyzing a product that evaporates so quickly.
Let’s look at it this way. I am currently in an office that is 13 by 8 feet with a 9 foot ceiling. The office is 936 cubic feet. If one pint of methylene chloride evaporated in the office it would be 25 ppm. Less than three quarts evaporated it would be 125 ppm. And the material evaporates about 90 times faster than water. So, one pint of methylene chloride evaporating with no ventilation would push it over the OSHA allowed limit.
It is easy to become desensitized to the smell of methylene chloride. The smell threshold is low but most tests estimate it is over 25 ppm.
Use concentrations in the air are often over the limit. The EPA accessed the upper end of consumer exposure at 233 ppm. Generally, exposures above 200 ppm show signs of neurotoxicity. In enclosed spaces these concentrations can be deadly.
Deaths
The EPA’s ruling states that they were trying to prevents deaths. OSHA and the EPA found 49 direct fatalities due to exposure between 1976 and 2016. This does not include people who may have died from health conditions or cancers produced by this product.
Although the EPA does not break out the occupations of the people who died, there has probably been very few deaths in the metal finishing industry. I do not have access to OSHA’s records but the information I have found shows that almost every death has occurred when someone ignores OSHA guidelines. There were some cases where someone fell into a storage tank or processing tank and died. These are industrial accidents beyond the scope of OSHA or the EPA.
Between 2000 and 2015, seventeen people died from using methylene chloride stripping bathtubs. They are working in an enclosed space using the chemical to strip off coatings on the bathtub.
Environment
It is not very biodegradable, but it does not bioaccumulate in animals and is a low hazard for aquatic toxicity. The Clean Air Act lists it a hazardous air pollutant. RCRA, the Resource Conservation and Recovery Act, that controls disposal regulations of chemicals considers it a hazardous waste and requires treatment or disposal of any residues. The Safe Drinking Water Act administered by the EPA set a goal of zero contaminant level in drinking water. They will enforce the rules on any level above 5 parts per billion. This is about 9 milliliters or 1/8 of a fluid ounce in an Olympic sized swimming pool.
Methylene chloride has a low atmospheric photochemical reactivity. This means that it does not create smog. Because of this it is not classified by the federal EPA as a VOC, although some states use different definitions of VOC and may classify it differently.
Who does this apply to?
The EPA differentiates between industrial/commercial users and consumer uses of products. A consumer is any person who uses a product for personal use without receiving payment. The use of methylene chloride in consumer paint strippers is estimated by the EPA at less than 10% of its total use. They estimate that only 7 chemical companies manufacture products for the consumer industry.
Any company with at least one consumer customer is considered a retailer. The EPA looked at 109 consumer paint stripping products and 54% of them contained methylene chloride.
Actual Regulations
The regulations do 4 things:
1) Prohibit any retail sales of products to consumers that contain methylene chloride. This includes all e-commerce. This includes all hardware stores and home improvement stores.
2) It can only be sold or distributed to commercial or industrial end-users or businesses.
3) The SDS must have a warning that it cannot be sold for consumer use.
4) Records must be kept relevant to the rules.
More action
The EPA published on Friday, March 15, 2019 a document called: “Methylene Chloride: Regulation of Paint and Coating Removal for Consumer Use under TSCA Section 6(a)”. This amends the EPA rules at 40 CFR Part 751. They go into effect 180 days from the date of the ruling.
They are not actually finalizing the rules for the commercial and industrial use at this time. The new rule only applies to the consumer over-the-counter use of the product.
The EPA is currently soliciting comments on training, certification, and limited access use of this material.
There are several other chemicals being reviewed under the same laws. One of them normal methyl pyrollidone, also known as NMP. While methylene chloride has caused many deaths over the years, NMP has caused zero deaths. The action on the more hazardous methylene chloride should give us some indication of the upcoming rules on other products.
Editorial
I agree with the decision of the EPA. I think that it is a balance between the safety of the public and the needs of the industry. However, methylene chloride has many health hazards that make it a material that make it undesirable for use in any application.
There has been a lot of misinformation produced by the news media, politicians, and other entities about methylene chloride. It is no longer a safety issue, it is now a political one. But it is a health and safety issue. The problems with methylene chloride and its carcinogenic effects have been known for decades but because of its strong industrial lobby it has never been effectively regulated. This is the first time that the government has taken any substantial action.
All the information on all the deaths I have found occur when the product is used in violation of the OSHA regulations. Essentially, death usually has occurred when the product is used improperly or illegally or when a tragic accident occurs. The deaths occurred from using the product against OSHA regulations and against the label recommendations.
OSHA regulations apply only to employees. Employers have a responsibility to give employees safety training and proper safety equipment. The employer only has to tell the employees the information, they are not required to force employees to use it. There is a common myth that OSHA regulations do not apply to companies under ten employees. Not all OSHA rules apply to very small companies but the exposure limits and safety equipment requirements do.
I am concerned that untrained “professionals” are allowed to use these products for “commercial” use. This can be an independent contractor who will probably have insufficient training and safety equipment. Industrial users are usually trained in using these products. Because of this people will continue to die.
I think the only solution is to have these products used in fixed locations, approved on site by the local EPA and with adequate ventilation. If you are going to use a product as hazardous as this you should be prepared to do so. Additionally, I do not think it should be allowed in residences.
Most of the deaths are non-employees. If someone has their own business or working in their own home and the OSHA regulations do not apply. In the instances where people who were not employees died, they still violated OSHA guidelines.
However, the product is so volatile that it is easy to reach exposure limits and be in violation of the guidelines. Most of the industrial facilities that I have been in are probably over the allowed concentration limit for the chemicals vapors produced by these chemicals. There were two instances that I found the facilities because I could smell the product from outside their building.
I believe this chemical has serious health hazards and is used carelessly in the industry. It is banned because of carelessness. It was banned due to the ignorance of the chemical hazards associated with it.
Knowledge will save your life. You don’t need regulations to do it.