Dear Health Protection Agency,
I believe that your methodolgy for the assesment of health effects from waste incineration to be fataly flawed. By using distance by proxy and comparing the health of all residents within a circular district with the incinerator at the centre effectively 'masks' the true effect.
If you take a council ward directly upwind of the incinerator and compare the infant mortality with a corresponding number of residents in a ward downwind of the incinerator there is alway, according to the figures supplied by the governments Small Statistical Unit, a detectable statistical difference.
Whilst I fully undersatnd that this 'raw' data does not take into account other confounding factors such as socio economic or environmentalpressures surely it is untenable to discount these figures.

Yours faithfully,

Jeff Meehan

Dear Freedom Of Information,

Hi Leigh,
Thanks for the confirmation that you are looking into my inquiry. Can I send you a few more details which might explain the situation better?

Yours sincerely,

Jeff Meehan

Dear Freedom Of Information,

Almost all locations have a non-uniform distribution of wind directions, which means that some areas will be largely downwind of an incinerator, and some areas will be largely upwind. Clearly those that are largely downwind will receive much more pollution than will those that are largely upwind.
If wind direction is ignored, then the average effect of the pollution will be much less, and may even be statistically insignificant.
In Halton windroses show that the majority of directions receive little or no wind. The main winds come
from the WNW and just E of S, each encompassing a sector of about 60º, which together is 1/3 of the total 360º.
Suppose, for the sake of argument (and exaggerating numbers to illustrate the effect), that the cancer risk in that sector is twice that of the remaining 300º because of emissions from an incinerator, e.g. 1:100. If this was compared directly with the 1:200 for the rest of the residents who are relatively unaffected the difference would be obvious.
However if all the residents risks are considered in total (1:100 + 1:200 + 1:200) = 1.33:100. So although the downwind residents are at twice the risk than those upwind by considering everyone in the circle, this statistic is masked.
If now we consider the (thankfully very low) statistical occurrence of infant mortality with a frequency in single figures per thousand of births, it can be appreciated why the conclusion that there is no measurable effect is arrived at.
One of the main studies on which DEFRA and others have relied for their assertion that the cancer risk from incinerators is negligible is that of Elliott et al. [1996]. They nevertheless reported a 37% excess incidence of liver cancer for people living within 1km of an incinerator, but put this down to possible misdiagnosis and residual confounding. The Elliott et al. paper is thus fatally flawed, as are all others that have not taken account of wind direction.
A recent paper by Roberts and Chen [2006] has derived a quantitative measure of risk from a modern waste incinerator, based on current allowed emission levels. The authors calculate that the overall risk of dying in any one year from incinerator emissions is 2.49x10-7.
Interestingly, they found that the main contributors to that risk were cadmium (72%), dioxins (17%), arsenic (10%) and polyaromatic hydrocarbons (1%). The risk of dying from incinerator emissions over the 25-year operating life of an incinerator is 25 times the annual risk, or 6.23 x 10-6, and the 70-year lifetime risk is 1.74 x 10-5.
Both of these values are well above the de minimis acceptable lifetime target level of 10-6 (i.e. 1 in a million) used by the U.S. Environmental Protection Agency [Castorina & Woodruff 2003]. It should be noted here that the U.S. E.P.A. target level is for cancer risk alone; however, the four toxins found by Roberts and Chen [2006] to contribute most to mortality from incinerator emissions are all known carcinogens, so the comparison is valid.

Yours sincerely,

Jeff Meehan