Survey of cyanotoxins in New Zealand water bodies between 2001 and 2004

Abstract

Contamination of drinking and recreational water bodies by toxic cyanobacteria is a significant water management issue in many countries. Until recently, knowledge of the occurrence of cyanotoxins and species responsible for cyanotoxin production in New Zealand was limited. In this study a total of 266 water and cyanobacterial mat samples collected from 227 different water bodies between 2001 to 2004 were analysed for cyanotoxins. Enzyme‐linked immunosorbent assays, liquid chromatography mass spectrometry, high performance liquid chromatography, and neuroblastoma assays resulted in the identification of microcystins/nodularins (102 samples from 54 different water bodies), anatoxin‐a (three samples from three different water bodies), and saxitoxins (48 samples from 41 different water bodies). The highest microcystin concentration was 36.5 mg litre^‐1. The detection of anatoxin‐a is the first definitive report for New Zealand. Only low concentrations of saxitoxins were detected. Results indicate that cyanotoxins are more widespread in New Zealand water bodies than previously reported, in particular when cyanobacterial blooms or benthic cyanobacterial mats are present.

Key words:

• cyanotoxins
• New Zealand
• cyanobacteria
• anatoxin‐a
• cylindrospermopsins
• saxitoxins
• microcystins
• nodularin