In its natural state, gypsum is a rather harmless building material that is even used in baking of breads.
But due to the ongoing construction boom in Kenya, large amounts of dangerous, artificial gypsum building materials are now being imported into the country.
Kenya Consumers Organisation executive director Francis Orago says the government should investigate this because similar concerns about the harmful, man-made gypsum building materials have been raised in other countries.
Gypsum is a soft white or gray mineral consisting of hydrated calcium sulfate. It
occurs chiefly in sedimentary deposits and is used to make plaster of
Paris and fertilisers, and in the building industry. It is actually the most widely used of all interior construction materials, mostly as a surface material for walls and ceilings and to fill cavities.
“We remember how asbestos rose from being a much-loved material in wiring and construction to a human health hazard,” Orago says.
Asbestos usage began in the 19th century as manufacturers’ and builders’ favourite material because of its desirable physical properties and was used in electrical insulation for hotplate wiring and in building insulation. Knowledge of its toxic effects caused its demise as a mainstream construction and fireproofing material in most countries. Kenya banned the use of asbestos in 2006.
And just like asbestos was popular prior to its banning, many people also use gypsum every day in construction.
The mineral is also used as an additive in foods such as ice cream, flour and white bread. Kenyans may also know gypsum as the whitish stuff found in surgical and orthopedic casts, toothpaste, cosmetics and drugs.
For gardeners, it can be used as a natural additive to soil to enhance its ability to retain moisture or to reduce the corrosiveness of the soil’s alkalinity.
Building materials manufacturer Erdemann Gypsum, which uses the natural gypsum to make its products, also confirms that toxic, artificial gypsum-based products are in Kenya.
The company said such building material are contaminated by low levels of the heavy metals present in coal.
“We should use building materials from natural gypsum, which is safe for our health," says Erdemann Gypsum managing director John Yang.
He asks the government to
inspect all imported gypsum products to ensure they are natural and are not contaminated.
Erdemann mines gypsum - its factory's main raw material - in Kitui. The company, which has factories in Kitui and Athi River, is among the only three firms approved to manufacture gypsum building materials in Kenya.
The other companies approved by Kenya Bureau of Standards are Deco Dura Creations and Shazaad which manufacture boards, plasters, cornices, corners and medallions.
Orago said Kebs and National Environment Management Authority (Nema) should protect the country from health dangers of the synthetic building products.
“Let the two agencies keenly study the issue and give the country the way forward,” he said. Orago added that should the government fail to issue direction on use of gypsum locally, his organisation will have to advise consumers accordingly.
In January 2013, the US passed a new law to prevent future problems with bad drywall (gypsum board) as a result of using contaminated gypsum.
If handled improperly, gypsum can cause irritation to the skin, eyes, mucous membranes and the upper respiratory system. Symptoms of irritation include nosebleeds, rhinorrhea (discharge of thin mucous), coughing and sneezing. If ingested, gypsum can clog the gastrointestinal tract.
Kebs uses international standards to monitor quality of gypsum building materials. The bureau says it uses the American Society for Testing and Materials' Standards and European Standards Specification for gypsum board, binders and plasters.
Yang says most imported gypsum products are from cheap artificial material and cannot meet these standards.
“The government should inspect imported gypsum products to ensure they do not have chemical contaminants," Yang said.
In April 2014, the American Consumer Product Safety Commission sent staff to China to obtain samples of wallboard manufactured there in 2005, 2006 and 2009. This is after a US government report indicated that a Chinese-made drywall used in more than 20,000 homes in that country could have caused nosebleeds, headaches, difficulty breathing and asthma attacks in tens of thousands of Americans exposed to it.
In 2011, the Unep conducted a study on the potential heavy metal content in synthetic gypsum, but reached no definitive conclusion.
However, the study said that chemical contaminants may be found in gypsum boards where other materials are added as fillers or flame retardants. In early 2008, some gypsum boards produced in China were found to emit sulphide gasses, according to the study.
China is the largest producer of gypsum followed by Iran, Spain, the US, Thailand, Japan, Mexico, Italy, Canada, Australia, Turkey, Russia, Egypt, India, France, Saudi Arabia, Brazil, Germany, Algeria, United Kingdom, Poland, and Argentina.