Member Article

FUNGAL CONTAMINATION AND COMMERCIAL LEASES

Fungal contamination: a complex problem
The detection of a fungal contamination problem in a building can be a complex operation. For example, recurring water infiltration due to leaks in a building’s outer envelope can create an environment that is conducive to the growth of mould in spaces not visible to the occupant, such as behind walls, in ventilation conduits, and in the plenums of the ventilation system.

Many companies offer a wide array of services for detecting fungal contamination, ranging from ambient air quality tests to sniffer dogs. Nevertheless, if the source of the fungal contamination is not adequately identified and all the necessary corrections are not made, the problem can recur. In such cases, the multiplication of decontamination operations can become very costly and result in a significant reduction in the peaceful enjoyment of the leased premises.

In some cases, the health of employees can be affected, which can lead to significant operational difficulties for the occupying lessee.

In November 2002, the Institut national de santé publique du Québec (the “Institute”) published a scientific report¹ on health risks associated with the presence of interior moulds. The purpose of this report, which is still current, was to provide support for public health responses to mould problems occurring in both residential settings and in public buildings. The fungal contamination considered in this report “(…) refers to the uncontrolled growth of moulds on structures, furniture or other materials usually free of humidity, and in ventilation systems,”² in non-industrial and non-agricultural indoor environments.³

With respect to the origin of fungal contamination in indoor environments, the Institute indicates that: “The main factor contributing to fungal growth therefore remains the presence of available water, which can be due to problems of chronic infiltration, excessive humidity, surface condensation or a broken pipe or a flood.”⁴ The Institute further notes that, at present, no reliable data exists to establish a threshold below which there is no effect on health, and there is no reference list to evaluate the health risk for a given mould species.⁵

The Institute concludes as follows:⁶

“The reviewed studies complement each other, confirm the scientific consensus described in the preceding paragraph and make it possible to state that indoor mould exposure is a health risk varying according to the species encountered, the exposure dose and the subjects’ individual susceptibility, and that the symptoms encountered affect several systems, especially the respiratory system. The main problems recognized as being associated with moulds are irritation, asthma exacerbation, and allergic and hypersensitivity reactions. Toxic reactions following a strong or repeated exposure as well as infections in severely immunodepressed subjects are also documented.”