New York Governor Andrew Cuomo has acquiesced to a ban of hydraulic fracturing (fracking) of shale to produce natural gas in his state based on "uncertainties" concerning the possible effects of the activity on public health. Essentially, the New York Department of Health (DOH) report Cuomo cites defaulted to the precautionary principle:
When an activity raises threats of harm to human health or the environment, precautionary measures should be taken even if some cause and effect relationships are not fully established scientifically. In this context the proponent of an activity, rather than the public, should bear the burden of proof.
Or as the report asserts:
Based on this review, it is apparent that the science surrounding HVHF [high volume hydraulic fracturing] activity is limited, only just beginning to emerge, and largely suggests only hypotheses about potential public health impacts that need further evaluation….
…the overall weight of the evidence from the cumulative body of information contained in this Public Health Review demonstrates that there are significant uncertainties about the kinds of adverse health outcomes that may be associated with HVHF, the likelihood of the occurrence of adverse health outcomes, and the effectiveness of some of the mitigation measures in reducing or preventing environmental impacts which could adversely affect public health. Until the science provides sufficient information to determine the level of risk to public health from HVHF to all New Yorkers and whether the risks can be adequately managed, DOH recommends that HVHF should not proceed in New York State.
What sort of "evidence" did the DOH rely on for its ban recommendation? For example, the DOH study cited two epidemiological studies that purported to find adverse effects on birth outcomes near fracked wells. One found infants born closer to fracked wells had lower birth weights, but no increase in congenital defects. The other found an increase in congenital defects, but not lower birth weights. The DOH then noted:
Taken together, the relationship between maternal proximity to HVHF well pads during pregnancy and birth outcomes, if any, is unclear.
Well, yes. The DOH also reviewed a number of studies dealing with possible exposures to air pollutants from fracking and basically could find none in which pollutants exceeded regulatory limits. The DOH of review of the effects of fracking on drinking water supplies uncovered no substantial evidence for increased concerns about human health from that source.
The basic strategy of the DOH review seems to be to cite a bunch of studies - most of which find no significant problems or are inconclusive at worst - and then declare that their non-findings are insufficient to calm the regulators fears. Or as the report notes:
The actual degree and extent of these environmental impacts, as well as the extent to which they might contribute to adverse public health impacts are largely unknown. Nevertheless, the existing studies raise substantial questions about whether the public health risks of HVHF activities are sufficiently understood so that they can be adequately managed.
Pure precautionary principle. A simpler formulation of the precautionary principle is: Never do anything for the first time. Basically, ignorance can be used as an excuse to stop anything of which one disapproves.