It is estimated that about 900,000 workers in the EU are potentially exposed to chromium VI. Studies of workers in chromate production, chromate pigment and chrome electroplating industries employed before the 1980s show increased rates of lung cancer mortality.

Chromium VI compounds are classified as Carcinogenic Category 1A, which means they are a proven cause of cancer in humans. Chromium VI exposure occurs through breathing it in, ingestion via food or water, or direct contact with the skin. Due to the strong corrosive properties, chromium VI has acute health effects as well. In addition, exposure to chromium VI can cause skin and respiratory sensitisation, like asthma, and can lead to specific organ toxicity to the lung, liver and kidney.

Where risks occur

Workplace exposure occurs mainly in welding and other types of ‘hot work’ on stainless steel and other metals that contain chromium VI. Other types of work with potential exposure are the use of pigments, spray paints and coatings. Other relevant areas of work are surface treatment applications of plastics and metals, e.g. operating chrome-plating baths. Exposure also occurs by abrasive techniques of chromium VI-coated materials, like abrasive blasting, sanding and grinding. Industries where exposure occurs are the functional plating sector, steel, shipyards, construction, concrete industry and shops for repair and painting of auto bodies, trucks, trains and airplanes.

More about the substance

Chromium VI is a form of the metallic element chromium. In nature, it is often present with other elements, like metals, in ores and needs to be industrially processed. The most industrial relevant compounds contain sodium, potassium, zinc, strontium, lead or ammonium. Chromium trioxide or chromic acid are common industrial used chromium VI substances. Chromium metal is added intentionally to alloy steel or is used in surface treatments to increase technical properties, like hardenability, heat and corrosion resistance. Chromium VI compounds may be used as pigments in dyes, paints, inks, and plastics. It also may be used as an anticorrosive agent added to paints, primers, and other surface coatings. Unlike chromium VI, another relevant but not carcinogenic form is chromium III, which can be transformed to chromium VI under oxidative circumstances.

How the symptoms can affect you

Breathing in high levels of chromium VI can cause symptoms like a runny nose, sneezing, coughing, itching and a burning sensation. Repeated or prolonged exposure can cause sores in the nose and result in nosebleeds and damage to the nasal septum. Skin contact causes severe irritation and oral intake can cause acute poisoning (gastrointestinal symptoms). Some employees become allergic to chromium VI. Inhaling chromate compounds may then cause asthma symptoms. Chronic dermal exposure to chromium VI can lead to poorly healing ulcers found after skin injuries; oral uptake can cause systemic effects on kidney and liver. Prolonged exposure to airborne chromium VI can cause lung, nasal and sinus cancer.

The latency period between chromium VI related cancers is up to 20 years after chromium VI exposure.

What you can do

The most effective way to prevent exposure is to substitute with chromium VI-free or lower-chromium VI products. For specific uses and if applicable, technical alternatives might be exhausted (e.g. physical vapor deposition, chromium III-plating etc.). If chromium VI-containing products cannot be substituted, the exposure to the substance should be reduced through engineering controls. For example, use an extracted welding torch and proper local and workshop ventilation systems. Continuously carry out correct exposure measurements, so that it is known when action should be taken. Investigate whether workers report early symptoms. Make workers continuously aware of the effects of exposure. In addition, train workers on hazards, safe work practices and on effective hygiene measures. Ensure that workers have adequate personal protective equipment, such as suitable respiratory protection, protective clothing and gloves. In some cases, a respirator may be required. Personal protective equipment should only be used as a last resort, after the possible technical solutions have been presented. Although chromium VI exposure mainly takes place via inhalation, skin contact should be consequently avoided as well.