Kiwi homes are being wrapped with plywood containing an arsenic treatment banned in several overseas countries because of toxicity concerns.
Bracing plywood treated with the preservative copper chromium arsenic (CCA) is increasingly being used for residential repairs and rebuilds in Canterbury. Both arsenic and chromium compounds pose a potential health hazard in certain conditions.
Public health concerns about CCA arose 10 years ago when arsenic was found to leach from the treated timber, often used for decks, framing and playground equipment.
Plywood bracing products have appeared on the market since then, becoming more popular after leaky homes concerns, and are now in common use.
CAA is either banned or has restrictions placed upon its use in the United States, Canada, and several European Union countries including France, Spain, Italy, Germany the United Kingdom and Ireland.