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A couple of days ago the results of a global survey began to hit the headlines; A worldwide survey of neonicotinoids in honey, Mitchell et al., Science 358, 109–111 (2017) 6 October 2017. The study was based on a collection of samples from 'local producers' all around the world donated by colleagues, friends, and relatives connected the the University and Botanic Gardens of Neuchtel in Switzerland. Of the 300 received, gathered from apiaries, markets, and commercial sources, 198 were selected, in theory representing a broad range of environments but also avoiding an over-representation of European-sourced samples. Most but not all the EU samples were collected before the 'ban' on neonicotinoid use on bee-visited crops. Only 7% had the name of the beekeeper provided. The researchers point out this 'citizen science' aspect meant they had only a hazy (or no) idea about the honey samples and their provenance, whether they were blended, what nectar sources might be present, or the time period involved. Nor did they have any idea of the potential pesticides the sample was exposed to, or how the sample was stored prior to them receiving it. They are limited in what they can conclude about the potential environmental contamination by their ignorance about the behavioural and ecological aspects that many have affected the sample. There are four New Zealand samples in the data. One from near Marsden Point for thiamethoxam. Two from near the Korowai-Torlesse Tusockland Park outside Springfield for imidacloprid. One between the Tekapo military camp and Mt Cook, positive for imidacloprid, thiamethoxam, thiacloprid, and acetamiprid. I've had a look and acetamiprid is not in the current ACVM list as registered for use in New Zealand. Imidacloprid has bee registered since 1992, thiamethoxam and thiacloprid since 2000, and clothianidin from 2003. The seven Australian samples presented a simpler picture, one with no detection, four for imidacloprid (one including thiacloprid), one with only thiacloprid, and one with only thiamethoxam. Of the 198 samples tested, 149 had a measurable amount of at least one compound - 75%. Several compounds were found in 60% of samples. It's curious that three tests, for Italy, Portugal, and Spain, list thiamethoxam as 'Not detected' (ND, rather than >LOD - Limit of Detection). In the other 987 tests results are reported as an amount or as below the limit of quantification (<LOQ). If the distinction is correctly made, in 990 tests 987 must positive (but not quantifiable), or 99.7% This is not the claim being made. They do say that 48% of their samples exceeded a 'biologically relevant dose. The biologically relevant dose they chose has been derived mainly from a study on bumble bee brains reporting harm to neurons after several days exposure. I'm not really able to say if their choice was a valid one, the evaluation of the scientific literature on this is very difficult. My only observation would be that there are good reasons to think, behaviourally and ecologically, bumble bees, honey bees, and other pollinators are not the same, and neither are the five neonicotinoids. In the New Zealand results, most are very low and seemingly not significant. The two thiamethoxam results are relatively high, but it's difficult to draw the conclusion they are significant from the table of concentrations given in the Supplementary Data. Overall I'd say this is an interesting attempt at answering some important questions about the use of these pesticides. That they have become so ubiquitous in (for NZ) the last 25 years is startling, and from samples in, to me, pretty unlikely places. The claim neonicotinoids have been found in 75% of their samples isn't helpful, in that newspapers and consumers just hear "contaminated honey". Science magazine reported the study with the headline "Nerve agents in honey". Whether or not we can say it is harming pollinating insects (it isn't harming people!), it is actually an indictment of the way in which we are managing our landscapes, and the fact that so many samples had two or more of the compounds says something about the persistent and pervasive nature of these pesticides. There is a case to be made for a well designed long term monitoring programme, even in New Zealand.