Grech Victor
Department of Paediatrics, Mater Dei Hospital, Malta.
Int J Risk Saf Med. 2015;27(1):35-44. doi: 10.3233/JRS-150641.
Fallout from atomic bomb testing may travel great distances before precipitating. Males are born in excess of females in a ratio that approximates 0.515 (M/T: male live births divided by total live births. Radiation increases M/T by causing lethal malformations that affect female more than male foetuses, decreasing total births. This study was carried out in order to ascertain whether the effects of increased background radiation levels from atomic weapon testing had any widespread effects on M/T and births in the Americas, Europe, Asia and Australasia in relation to the Partial Test Ban Treaty of 1963.
Annual live births by gender were obtained from a World Health Organization dataset and annual number of atomic bomb tests were also obtained (historical data).
Overall, 94.5% of births studied showed a uniform reduction in M/T between the early 1950s to the late 1960s, followed by an increase to the mid-1970s, with a subsequent decline. A negative correlation of M/T with total births was found in 66% of births studied, and these were the regions which exhibited the rising M/T pattern in the 1970s. The birth deficit for countries with significant correlations of total births with M/T (North America, Europe and Asia) was estimated at 10090701.
A rising M/T was found in most regions in temporal association with atomic weapon testing. Most of these regions also had an associated decline in total births. Elevated levels of man-made ambient radiation may have reduced total births, affecting pregnancies carrying female pregnancies more than those carrying male pregnancies, thereby skewing M/T toward a higher male proportion.
原子弹试验产生的放射性沉降物在沉降前可能传播很远的距离。出生的男性数量超过女性,男女比例约为0.515(M/T:男性活产数除以总活产数)。辐射会增加M/T,因为它会导致致命的畸形,对女性胎儿的影响大于男性胎儿,从而减少总出生数。本研究旨在确定1963年《部分禁止核试验条约》相关的原子弹试验导致的背景辐射水平增加是否对美洲、欧洲、亚洲和大洋洲的M/T和出生情况产生了广泛影响。
从世界卫生组织的数据集中获取按性别划分的年度活产数,并获取年度原子弹试验次数(历史数据)。
总体而言,在研究的出生情况中,94.5%显示出从20世纪50年代初到60年代末M/T均匀下降,随后在70年代中期上升,随后又下降。在66%的研究出生情况中发现M/T与总出生数呈负相关,而这些地区在20世纪70年代呈现出M/T上升的模式。总出生数与M/T显著相关的国家(北美、欧洲和亚洲)的出生赤字估计为10090701。
在大多数地区发现M/T上升与原子弹试验在时间上相关。这些地区中的大多数总出生数也相应下降。人为环境辐射水平升高可能减少了总出生数,对怀女胎的影响大于怀男胎的,从而使M/T向更高的男性比例倾斜。