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Standing water and wet materials are breeding grounds for micro organisms such as viruses, bacteria, and mould. They can cause disease, trigger allergic reactions and continue to damage materials long after a flood subsides. Mould brought into the home during flooding penetrates deep into soaked, porous materials. Mould spores are later released into the air or water and can subsequently cause illness.

What is mould?

Sometimes referred to as mildew, moulds are a group of fungi that grow in the right conditions warmth and humidity. Mould comprises thousands of species and is mostly detected from a musty odour. Mould produces spores that spread through the air and form new colonies (mould growths).

How does mould get indoors?

Mould comes from outdoor sources and needs moisture to grow. Moisture occurs as a result of water damage, dampness, or high humidity. Lowering the humidity by using air conditioners and dehumidifiers will reduce the likelihood of mould growth. When condensation collects on cold surfaces such as bathroom tiles, mould starts to grow. Large qualities of mould growth may cause odours, damage furnishings and finishes, and cause health problems.

Can mould be toxic?

Some moulds produce toxic substances called mycotoxins. In rare cases, high or chronic airborne exposure has been associated with illnesses, although for most people sensitive to moulds, allergic reactions, similar to common pollen or animal allergies, and irritation are the most common health effects. Flu-like symptoms and skin rash may occur and mould may also aggravate asthma. Most symptoms are temporary and are eliminated by correcting the mould problem.

Who is affected by mould?

People with special health concerns should consult a doctor if they are concerned about mould exposure. Those who may be affected more severely and quickly than others include infants and children, the elderly, pregnant women, people with respiratory conditions, allergies, or asthma; and those with weakened immune systems such as chemotherapy patients, transplant recipients, or those with autoimmune diseases.

How can I prevent mould growth?

Keeping areas as clean and dry as possible is essential in controlling mould growth. As a general rule, materials that are wet and cannot be thoroughly cleaned or dried should be discarded.

Replace absorbent materials that become mouldy (such as ceiling tiles, wallboard, and carpeting). When cleaning mould, wear gloves, eye protection, and a dust mask (an N95 or P100, the N95 masks are available at some local supermarkets and protect against dust, mould, and fibreglass inhalation). Extensive mould growth in buildings should be corrected by removing contaminated materials, cleaning surfaces, and completely drying the areas.

What is the best way to cleanup?

The cleanup process involves thorough washing and disinfecting of all surfaces--walls, floors, closets, shelves, and contents. In most cases, common household cleaning products and disinfectants can be used. Be careful about mixing household cleaners together; follow label instructions carefully and ensure fresh air by opening windows and doors. If possible, use fans both during and after the disinfecting, cleaning, and sanitizing process.