An interview with Dr Nick D Kim, Senior Lecturer at the School of Health Sciences, Subject Leader – Environmental Health Massey University (Wellington).
Your career spans academia, regional government, national policy and independent advisory roles. Which experience has most shaped your approach to environmental chemistry and public health decision making?
I’ve had a few, but one point where my understanding shifted was in events leading to development of New Zealand’s national cadmium management strategy.
At the start of that process, I was a regional council scientist responsible for a technical report which was impossible for regulatory agencies and policymakers to ignore. Like many scientists, my focus was the technical aspects, and my naïve assumption was that—as long as you set the facts out clearly—everyone will see the obvious problem. As many readers will know, life doesn’t work that way, and whenever technical problems are raised, most people see the scientist as the problem. In fact, at one point the CE of a different agency demanded that Waikato Regional Council take moves to ‘reign their scientists in.’ History is littered with a trail of dead truth-tellers, so I got off easy. I was only punished by being made part of the National Cadmium Working Group.
Through that process and others, however, I did develop a more pragmatic and probably accurate view. Science can and should inform policy making—it can characterise the problems, trajectories, and the range of possible solutions—but it can’t tell you how you must act. Decision-making is also about human values and priorities. In a regulatory setting these are often embodied into various statutes, policies, and plan rules. Formal decision-making sits in that context. Right now, New Zealand is going through some major reforms in its resource management legislation. One way of viewing these is as a re-balancing of the weightings applied to specific community values: human health protection, ecosystem health, trade and economy, and the balance between individual autonomy and regulatory intervention.
Other areas that have shaped my approach to things include my involvement with standards and guidelines, and the bewildering diversity of diffuse contamination issues that regulators are faced with. I’ll bring up aspects of both of these in my talk.
You are Senior Lecturer in Applied Environmental Chemistry at Massey University’s School of Health Sciences in Wellington, New Zealand, where you oversee Massey’s environmental health training. What’s that all about?
One thing I always have to start with is an explanation.
‘Environmental health’ is a long-standing name for the professional discipline focused on protection of human health from threats in the environment, be those man-made or natural. The name itself is a case-study in misdirection. Most people justifiably think that environmental health must be about the health of the environment, but no. There are some overlaps with both environmental science and ecosystem health, but in environmental health, the focus is on the protection of humans, from the wider environment, which (I think we can all agree, at least) is always up to something. For the academically-inclined, a peer-reviewed journal in this area is Environmental Health Perspectives.
Now we have that out of the way—the two main groups of professionals that work in this area in New Zealand are Environmental Health Officers (EHOs) who are employed by our 67 territorial authorities (city councils, district councils, and unitary authorities) and our Defence Force (NZDF), and Health Protection Officers (HPOs) who work for Health New Zealand – Te Whatu Ora. HPOs usually work in teams overseen by a Medical Officer of Health (MoH): a medical professional who specializes in environmental health. Australia and many other countries have parallel systems, so there is some traffic of environmental health practitioners between different countries.
Massey offers the only qualifications that meet New Zealand’s requirements for EHOs. The origins of this training go all the way back to 1948 when Wellington Technical College put the first courses on, and the professional term was ‘Hygiene Officer.’ Through the years the coverage evolved to meet changing roles and health protection challenges, and ownership also changed to Wellington Polytechnic, and then on to Massey University when the two amalgamated in 1999. Our students are spread throughout New Zealand. Study is by distance learning and field trips, but students also come together for contact workshops that we run at Massey’s campus in Wellington. The training itself is quite broad and covers applicable laws, toxicology, epidemiology and communicable diseases, food safety, water and waste treatment, post-disaster management, and environmental monitoring—of air and water quality, noise, contaminated land, and several other areas. We have a small but dedicated group of academic staff who teach in this area, and I’ve been overseeing Massey’s two environmental health programmes for just over a decade.
You’ve contributed to a range of national standards and guideline reviews. What do you see as the biggest misconception about how standards should be interpreted and used in practice?
Several problems routinely come up, and many of your readers will be familiar with these.
The most common is that most people, including media, assume that exceeding a human health standard means that there’s an immediate risk. There are exceptions of course (do pay close attention to all thresholds for hydrogen sulphide gas!) but in most cases, most of the time, the standard will be highly conservative—they’re designed to accommodate a low-level lifetime exposure, potential for chronic toxicity, to the most vulnerable organ, with safety factors.
This misconception will be an ongoing source of confusion, and that is totally understandable because most people aren’t contaminated land experts or toxicologists. There’s also not much guidance about acute risk levels, so for a quiet life most practitioners won’t try to argue the point. However, whenever such an issue has a public-facing communications component, you’ll almost always see a direct statement along the lines ‘there is no immediate risk.’ Every time you see that statement, it’s to counter this common misconception.
Units and context also matter, but again not to most people. There is usually no appreciation that a picogram is 1000 times smaller than a nanogram which is 1000 times smaller than a microgram (and so forth); or why that could be worth knowing about.
Assumptions about exposure pathways are also key to interpreting most standards—but (there’s a theme here) the public doesn’t care. This is also understandable because we shouldn’t expect everyone to be experts in environmental impact assessment, and we are all pre-wired to be cautious about contamination and contagion. For the most part, that bias serves us well. But high-profile contaminated sites will often cause a lot of community concern, even when there are no possible exposure pathways. In cases like this the standard may be misapplied, in the sense that potential for actual harm presupposes the presence of both pathways and receptors.
Other problems often relate to interpretation. Three examples:
- Some substances occur naturally, and this context can be important. We had a case where a kindergarten arranged for a soil lead test, discovered that lead was present, and had their existing soil excavated and replaced with farm soil. The thing was, when the case finally percolated through to the media and we asked to see the test result, we found that lead in the original soil that went to a landfill was 15 mg/kg—a very typical natural background concentration for uncontaminated New Zealand soils. From regional monitoring we were aware that the replacement soil from the farm would have contained much the same concentration of lead, but additional cadmium.
- Most laypeople also stumble over lab reports, particularly the ‘less than’ (<) sign and how to interpret non-detects. I had a case where a guy phoned to vent at me (he was yelling at everyone), because a property sale fell through and he’d lost $15,000. He was especially offended about the concept of detection limits. As part of the sale agreement the property had been tested for methamphetamine residues, based on standard 100 cm² wall swabs. The lab results showed nothing but non-detects in every sample, but neither the real estate agency nor anyone else in the interpretive loop understood that the result ‘<0.05 µg’ means that meth wasn’t detected, to that level. They all took the report to mean that meth had been found,in every sample.
- Crossing over to professional practice, there can be differences in emphasis between regulators and practitioners around testing reliability, and sample representativeness—including how to deal with results that may be analytical outliers, or are indistinguishable from the standard (given sampling uncertainties and analytical error); and what the sample results can or should be taken to represent (in relation to the sample site itself), and whether you’re trying to prove that the site meets a standard (allowing for error), or has not yet been shown to exceed a standard (allowing for the same error).
Public health risk communication is often challenging. What tools or approaches do you find most effective when explaining complex environmental or chemical risks to managers and the public without overstating or understating the issue?
This can depend on the scale, which ranges from one individual to a concerned nation-state.
For big events there is a well-established playbook, or at least a set of principles that aren’t always followed. Whatever the situation, we tell our students that results from monitoring often lead to the need to communicate with people, and there are good and bad ways to do that. Good communication from a public agency is clear, open, honest, and respectful—it involves connecting with people to keep the focus on working through to a solution. Medical Officers of Health are often excellent at this. Poor communication can be a range of things, but typically multiplies confusion or concern, and makes a situation worse.
Sometimes people may need to be informed of the existence of a risk as a first step to managing a problem. On other occasions people become concerned about things that have no health significance. The results of almost any environmental monitoring can be underappreciated or catastrophized, understood or distorted, complicated or oversimplified, or used as a political football. Reactions may vary from disinterested to outraged. But personally, I’ve found that risk communication works best when you give people some simple ways of thinking about risk, rather than just numbers or reassurances. Context is often central: carefully chosen comparisons and simple imagery can help people understand scale without dismissing their concerns. Some specific approaches I’ve deployed more than once that your readers may have used themselves are:
- The idea that ‘the dose determines the poison’
- Explanation of how harm occurs, especially the need for an exposure pathway
- The impressive low-level reach of modern analytical chemistry techniques
- The idea of there being a health-risk spectrum, not all or nothing
- In some cases, comparison to other low-level exposures
- For naturally occurring substances, the context of baseline intakes
- If confident – a simple statement of opinion about health risks
- If confident – a ready answer to whether you’d let your kids live there.
There are (of course) cases where people may be hard to convince about the presence of a potentially serious threat, so this can go both ways. But much of the time ideas like the need for an exposure pathway are often genuinely helpful for both managers and the public.
When the tension’s high it’s always tempting to lighten the mood. Resist that impulse. Try to avoid smiling for any cameras, being too upbeat (it can come across as dismissive), or cracking jokes – as befits the moment. So if you are asked question number 8,do not answer: ‘Yes, because I don’t like my kids.’
Also bear in mind that some people will not be looking for a good-faith discussion, and that’s fine. Every human (me included) can marshal a wide array of arguments to support a position that they’ve already decided on. Common drivers are outrage, and social group affiliation, the ‘us versus them’ dynamic that both primatologists and sociologists can tell you more about. We can only do as much as we can. Listening to people’s concerns, and being respectful and open, all go a long way—but we can’t suspend our own professional judgement to accommodate every opinion or belief.
Can you share your concerns with fluorine in agricultural soils, and potential impacts these may have on trade and the wider economy?
Fluorine is a great example of why we could do with better problem-definition in defining guidelines or establishing limits, and I’ll use this example as part of my talk. Briefly, since the advent of superphosphate topdressing over seven decades ago, levels of fluorine in agricultural soils have been gradually climbing, year on year.
Superphosphate strongly promotes pasture growth, but fluorine is a natural contaminant of the phosphate rock feedstock – and so becomes part of the product. A typical fluorine concentration in superphosphate is 1.5%, or 15,000 mg/kg.
Accumulation of fluorine in long-established pastoral farm soils isn’t a direct or indirect issue for human health, and for the most part soil ecology is apparently doing well enough – though fluorine is phytotoxic. Pasture growth in some areas is probably already being suppressed but this factor will be hidden, because (as noted!) the source itself is a fertiliser; it has the opposite effect.
The real problem here is that cows and other grazing livestock eat more soil each day than your typical toddler. With a 15 kg toddler in the contaminated land context, we’re looking at 50 milligrams per day of incidental soil or dust ingestion, in New Zealand’s NESCS. With a 540 kg cow, it’s about 650 grams of soil ingested per day, as part of normal grazing. Even allowing for the body weight difference, that’s quite a lot of soil going into that cow. Per kilogram of body weight, the cow is taking in 360 times more soil each day than the toddler.
You might think that such excess could have the potential to cause few problems, and you might be correct. In some areas of the world with high natural fluorine in soils, it’s not possible to graze livestock. The key impact is chronic fluorosis, caused by fluorine’s ability to deform an animal’s teeth and bones. Severely impacted animals lose condition and (in severe cases) die.
Fortunately, in Australia and New Zealand we’re not there yet. However, in long-standing dairy farming areas with a long history of superphosphate use (Waikato, Bay of Plenty, Taranaki), we’re well on the way. Some research already points to an unexplained apparent uptick in the incidence of bone fractures in cattle which may or may not relate, but we can envisage more significant problems than those in a few more decades of superphosphate use. This in turn has implications for the future viability of livestock farming in some areas, which links the problem to trade and economy.
Now, sketching out the possible effects of a soil contaminant in this way is really an exercise in problem-definition. Potential outcomes depend on both the contaminant and the environmental exposure context, and for some situations the problems are not at all apparent until you delve. Fluorine relates to health of grazing animals, and primary production. For other contaminants the biggest problem is somewhere else. For cadmium, a significant one is that food standards can be breached in a proportion of grains and horticultural crops. For PFASs, a key element is its ability to leach to groundwater, over decades. In New Zealand’s legislative future, regulatory standards called ‘environmental limits’ loom large, but how they’ll be developed is still an open question. In my talk I’ll be advocating for being smart about how we develop those, starting with the contaminant and its context. I’m also a fan ofguidelines, which can be more useful and effective than standards, in many cases.
What are you most looking forward to at the WasteMINZ/ALGA Conference, and what key themes or insights can attendees expect from your keynote?
What I enjoy about these events is the range of professional expertise that comes together in the one place. That’s something to value because it’s great to get a sense of the depth in another specialty, where my own understanding falls off and someone else’s takes over. Cross-disciplinary meetings of this type don’t happen organically. It’s not like you’re out walking the dog and unexpectedly come across an impromptu meeting between a contaminated sites specialist, a groundwater hydrogeologist, a wastewater engineer, a regional council scientist, a compliance officer, and a legal expert or planning and policy analyst. (Which sounds like the start of a complicated ‘walk into a bar’ joke…so now I’m wondering about the punchline…)
As for my keynote, I’ll be aiming to unpack the big (‘once in a generation’) shift happening in New Zealand’s environmental management under the Resource Management Act reforms – most specifically what the new framework means for how we will set environmental limits. First, attendees can expect a few core insights on guidelines and standards themselves. I’m hoping this will be useful for practitioners who haven’t delved into this area before. I’ll explain why the notion of purely ‘science-based’ limits is a bit of a myth. Science is crucial, but all limits sit within policy frameworks. I’ll walk through different approaches to setting limits, the multiple purposes soil limits might serve, and some quick case studies – how a methamphetamine guideline suffered ‘purpose creep’, the arsenic drinking-water standard embodies pragmatic compromise, and that soil fluorine example of why it’s important to spend some time working out what the problems might be. If I’m doing my job, I’ll bring this back to the context of our resource management reforms, which aim to expand the policy side of the equation in the limit-setting process. Time will tell and we’ll see how all of the reforms will work out in practice, but I’m hoping my talk sparks some good discussion across the room – especially given the mix of expertise at the conference.
Why is it so important that events like this conference are held in New Zealand?
Events like this WasteMINZ + ALGA Conference are especially important in New Zealand because they gather – in the one place – the diverse mix of people who actually shape how we manage waste, resource recovery, contaminated land, and groundwater across Aotearoa and beyond: regional council scientists and regulators, national policymakers, consultants, industry operators, academics, and legal/planning experts from both New Zealand and Australia.
The inclusion of strong Australian participation through ALGA is a real strength; our trans-Tasman colleagues bring valuable expertise, different regulatory perspectives, and lessons from a wide range of climates, soils, and land uses, and remediation approaches. Sharing approaches across our jurisdictions like this make for rich discussions. They can help us to define best-practice envelopes, try something different, and/or avoid reinventing the wheel. A conference like this can be a catalyst for meaningful progress in both environmental health and natural resource management.
Dr Nick D Kim | Senior Lecturer | School of Health Sciences
Subject Leader – Environmental Health
Massey University (Wellington)
Dr Nick Kim is a Senior Lecturer in Applied Environmental Chemistry at Massey University’s School of Health Sciences in Wellington, New Zealand, where he oversees environmental health programmes, teaches topics in toxicology, environmental monitoring and risk assessment, and supervises postgraduate research. Holding a first-class BSc(Hons) and PhD in Environmental Chemistry from the University of Canterbury, he has over three decades of experience bridging applied environmental chemistry, human health risk assessment and natural resource management. His career includes 11 years lecturing at the University of Waikato, a decade as Science Advisor at Waikato Regional Council (where he led contaminated site investigations, regional air/soil/water monitoring and made contributions to national standards such as the NES for Contaminants in Soil), and 13 years at Massey, together with a six-month secondment as Senior Policy Advisor at the Ministry for Primary Industries. Dr Kim has provided technical support for a wide range of government initiatives, acted as an independent hearings commissioner under the RMA, and contributed to reviews of methamphetamine testing practices, ecological soil guideline values, and chemical regulation in Aotearoa. In his keynote he will draw on this practical and policy experience to examine the transition in New Zealand’s environmental limits under the reformed resource management framework, highlighting the inevitable interplay of science, policy choices, community values and practical compromises.
