Micro Care Marketing Services distributes the Vertrel^® family of solvent cleaners across North America. These chemicals are manufactured by the DuPont Company of Wilmington, Del. The key ingredient in Vertrel^® family is the patented fluorocarbon molecule known as HFC-43-10mee. This fluid is completely ozone-safe and has a low global warming potential. It is used as an alternative to CFC-113, methyl chloroform, hydrochlorofluorocarbons (HCFCs) and perfluorocarbons (PFCs) in many critical cleaning, drying, carrier fluid and other high-value specialty uses where reliability is paramount.

Based upon toxicological research reported below, DuPont has established an Acceptable Exposure Limit (AEL) of 200 ppm, using the 8- and 12-hour time weighted average (TWA) methodology. Also, based on the seizure-like behavior observed in the single exposure study, a ceiling limit of 400 ppm was established. Users can be confident that HFC-43-10mee has low toxicity if exposures are limited to the recommended 200 ppm time-weighted average exposure, and if users never exceed the 400 ppm ceiling.

Despite this research, many customers are skeptical of the safety and toxicity claims made by any company. The purpose of this page is to explain some of the details of the toxicity studies which have been peformed on HFC-43-10mee so users can judge for themselves the safety of this important new technical development.

Note: The following information is a summary of very technical toxicological reports. It is intended for sophisticated customers with substantial training in biological sciences and toxicity testing. If you have questions, show this summary to your health and safety manager.

A series of acute toxicity studies have demonstrated that HFC-43-10mee has low toxicity. HFC-43-10mee is a slight skin and eye irritant. HFC-43-10mee has low acute inhalation toxicity as measured by the lowest exposure concentration that causes mortality in experimental animals, the approximate lethal concentration (ALC). The details include:

• The 4-hour ALC for HFC-43-10mee is 10,000 ppm in rats.
  
  
• In a 90-day inhalation study in rats exposed to 0, 500, 2000, or 3500 ppm HFC-43-10mee, no effects on body weights, hematology, organ weights or histopathology were observed.
  
  
• At concentrations of 2000 ppm and greater, transient seizure-like behavior was observed.
  
  
• At 3500 ppm HFC-43-10mee, reduced motor activity was observed the day after exposure.
  
  
• The low concentration of 500 ppm was a no-observed-adverse effect level (NOAEL).
  
  
• In a subsequent study, rats were exposed for a single 2-hour period to HFC-43-10mee concentrations of 1000, 1500, 2500 or 4000 ppm. Seizure-like behavior was observed at 2500 and 4000 ppm, but not at 1000 or 1500 ppm.
  
  
• Based on these results, a 2-week repeated inhalation study (6 hr/day, 5 days/week) in rats was conducted at 1000 ppm. No adverse clinical signs of toxicity were evident throughout this study.

Based upon these studies, DuPont Company has concluded that HFC-43-10mee has low toxicity.

Several genetic toxicity studies have also been completed with HFC-43-10mee and these included an in vitro Ames assay, a chromosomal aberration study with human lymphocytes, and an in vivomouse micronucleus. No mutagenic changes were observed with HFC-43-10mee in any of these studies. Therefore, the evidence from these studies suggest that HFC-43-10mee is not genotoxic.

Inhalation of halocarbons and hydrocarbons followed by intravenous injection of epinephrine, to simulate human stress reactions, can result in a cardiac sensitization response in experimental screening studies with dogs. For HFC-43-10mee, no cardiac sensitization response was observed at 1000 or 5000 ppm. At 10,000 ppm, seizure-like behavior was observed in the dogs, thereby preventing detection of a cardiac sensitization response.

The results from a developmental toxicity study with HFC-43-10mee show that this material does not have embryotoxic or teratogenic effects in rats. At 2000 ppm and greater, seizure-like effects were observed in the pregnant rat. Offspring from maternal rats exposed to 3500 had slightly lower body weights compared to control rats. However, no compound-related fetal malformations were observed at any exposure concentration.

The most significant observations involving HFC-43-10mee are:

• the seizure-like effects observed at high exposure levels in several studies,
• the reduced motor activity observed in the 90-day study,
• the reduced fetal body weights observed in the developmental toxicity study,
• the 500 ppm NOAEL,
• the low acute inhalation toxicity, and
• the lack of mutagenic changes.

Based upon these findings, DuPont has established an Acceptable Exposure Limit (AEL) of 200 ppm, using the 8- and 12-hour time weighted average (TWA) methodology. Also, based on the seizure-like behavior observed in the single exposure study, a ceiling limit of 400 ppm was established. Uses can be confident that HFC-43-10mee has low toxicity if exposures are limited to the recommended 200 ppm time-weighted average exposure, and if users never exceed the 400 ppm ceiling.

Because of these excellent toxicity results, HFC-43-10mee is accepted under the U.S. EPA's SNAP program and listed in the national chemical inventories of most countries, such as TSCA in the U.S., ELINICS in Europe, Chemical Substances Control Law (MITI/MHW) in Japan, DSL (notified) in Canada, NICNAS in Australia, and TCCL in Korea.

Despite these positive results, users are strongly recommended to design and implement a pro-active safety program for these solvents and for all of the chemicals used in their facilities. In particular, this training should include training about the chemicals, their proper use, issues surrounding flammability, toxicity, skin contact, eye contact and/or accidental ingestion, and safe handling and storage.

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