OHS Canada Magazine

The Limitations of Water Washing for Managing Corrosive Chemical Injuries

May 22, 2019
By David Wootten

Chemical-exposure injuries occur far too often in workplaces across Canada. There are almost 50 fatalities every year as a result of short and long-term exposure to aggressive chemicals in the workplace. In fact, Canada averages about 2,500 lost-time claims per year (AWCBC 2016) from exposure to chemicals, resulting in thousands of lost-time days.

Reducing or eliminating these risks through engineering controls, proper training and wearing the right personal protective equipment are critical to preventing serious injuries and illness caused by exposure to dangerous chemicals, one of the most common being accidental contact to human skin and eye tissue.

Workplaces with chemical risks are required to make emergency showers and eyewash stations available. Using water to remove an aggressive chemical agent from skin or eye tissue reduces burn injuries caused by strong acidic or caustic agents. The following are the benefits of flushing with water:

  • Copious amounts of flowing water provides a mechanical removal effect
  • Dilutes chemical agents – not neutralize
  • Water is universal and generally considered safe to help remove a chemical from skin/eye tissue

But is flushing our skin or eye tissue with water always the best option? It certainly is if if only water is available. While flushing with potable water improves outcomes, it does not always prevent serious burns and permanent injuries following exposure to concentrated corrosive agents. The backend effect of water washing has its limitations; therefore water is considered a passive rinse. So what are these limitations?

  • Water can only dilute a chemical agent. But using water to dilute a chemical, especially one that is concentrated, can take a long time to restore the physiological pH level of the exposed skin or ocular tissue. The longer this transition takes, the greater the potential for injury and the need for medical aid.
  • Water is by nature “hypotonic” to our body’s fluids, especially blood and tears. This means that water has a natural-flow diffusion that penetrates the chemical deeper into tissue cells.
  • Water dispensed from emergency showers and eyewash equipment is not sterile. Often, it is not even clean enough to be used on exposed burn tissue, especially eye tissue.
  • Water can create a “squeegee” effect that drags the chemical agent down the body extending the area of injury.

An alternative solution that manages corrosive chemical splashes to human skin and ocular tissue is Diphoterine® — a decontamination solution specifically designed to prevent chemical burn injuries and subsequent lost-time days. As an amphoteric solution with hypertonic and chelating effects, Diphoterine® solution converts the passive backend effects of water into active effects. It is the simultaneous action of mechanical removal, reversing the tissue flow and the binding capacity on the acidic or basic ions that create this active effect, which helps to eliminate or dramatically reduce corrosive burn injuries.

Diphoterine® solution is equally effective on all acidic, basic and irritant group chemicals such as reducing agents, oxidizers and solvents.

The most recent study supporting the efficiency of Diphoterine® solution came from the British Burns Association (BBA), which updated their recommendations for managing chemical burns. “In the absence of amphoteric solutions, irrigation should be performed with saline solution. If neither is available, then irrigate with water,” the study stated.

 The French Society of Ophthalmology also updated its guidelines for chemical eye injuries, acknowledging that “Diphoterine® is a preservative-free, sterile and amphoteric solution that binds acids and bases, restoring ocular pH within seconds or minutes,” it states. “Amphoteric solutions are most adaptive to emergency rinsing of chemical burns.”

When a chemical-exposure injury occurs, the duration of contact and what is done during that time is critical to preventing serious long-term injuries and lost-time days. Properly functioning eyewash stations and emergency showers remain essential rinsing equipment in worksites where corrosive chemicals are present. But it is also important to know that Diphoterine® solution is superior over passive water washing and there is growing evidence and studies supporting its efficacy.

Diphoterine® solution has been adopted by many industry sectors throughout Europe, the United Kingdom, Brazil, Mexico and Australia. It’s time for Canada to catch up.

 David Wootten is Prevor Canadian product manager with Levitt-Safety Ltd. in Oakville, Ontario.