Introduction to ‘Pretty Poisons In The Yard’ Series.

As the world reacts to global warming concepts by changing how and what is planted and cultivated, there exists the risk of creating new niches for new diseases or the reoccurrence of old forgotten toxins.

The growing horticultural and human health trend world-wide, is to classify, and hence to recommend, plants according to their aero-allergen potential with selection of plants biased towards those having an OPALS (Paul Ogren Plant Allergy Score) of 4 or less. This classification is highly effective in selecting for plants which provided less irritation to human airways and hence are favored by Asthma organizations globally as part of their ‘Low Allergen Garden’ concept.

The problem arises that, unless full and equal attention is also paid to the potential irritant or contact reaction scores of these plants, relying solely on a low aeroallergen OPAL score to recommend a given plant has the potential to increase the risk of adverse physical contact exposure to our veterinary patients. We can warn children and adults to avoid handling or ingesting certain plants: the same does not hold true for the inquisitive or bored family pet who wanders through the garden, brushes the irritants or contacts onto their skin and/or ingests the toxin when chewing or playing with these plants.

It is imperative that veterinary practitioners remain alert and responsive to this potential to induce pain and suffering in our pets.

Equally, it is important to accurately identify suspect plants (through referral of suitable specimens to expert professionals) to avoid confusion over which plant may have induced an adverse response in our patients. One should not rely on common names as common plant names may not accurately identify causative species. The common name of ‘Sky Flower’ for some Plumbago plants is also shared with as a common name for shrubs of the Duranta species. In the former case, severe blistering skin conditions can occur, whereas in the latter case, whilst mild transient skin irritation may occur, it is Neurotoxicity following ingestion of the Duranta fruits and leaves that is the major concern.

In Australia, free identification of up to six specimens, or two hours work per year, is provided to members of the public by government herbariums such as the National Herbarium in the Sydney Botanic Gardens. The specimen is data-based, incorporated into the herbarium and given a quotable voucher number to enable unique referencing to that particular specimen in any research or publication. Harvesting and drying of the plant material suitable for submission is explained in full and simple steps in many botanical text books. I use Ross McKenzie’s Australia’s poisonous plants, fungi and cyanobacteria as my guide.

I have posted on the five most common Pretty Poisons that caused the most problems to our patients;all of these five plants/shrubs are low aeroallergen, but all of  can either cause  skin lesions and/or neurological signs.