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The Dutch part of Kempenland has been exposed to cadmium pollution since the last century. Experimental data suggest effects by cadmium on reproduction such as diminished fertility, decreased foetal growth, and specific malformations. Use was made of a historical cohort of dairy cows, ascertained from a surveillance program conducted by the regional Veterinary Health Service between 1976 and 1986. Ten dairy farms in the cadmium region were matched by size with 40 dairy farms from a reference area. Logistic models were used to calculate Odds (OR) and Rate Ratios (RR) and their 95% confidence interval. In total 4,039 exposed and 15,552 reference gestations were compared. The reasons for the slaughter of 574 exposed and of 2,824 reference cows were ascertained. A lower twinning rate [OR = 0.63 (0.47-0.84)] was found and more birth complications, for both calves [OR = 1.50 (1.25-1.80)] and cows [OR = 1.49 (1.24-1.79)]. More inseminations [OR = 1.20 (1.01-1.43)] were needed for conception in the exposed area. Deaths among twins [OR = 1.66 (0.90-3.07)] were not significantly higher. Perinatal death, premature death, age at, or reasons for, slaughter were not consistently different. These results are consistent with those of other observational and experimental studies. Extrapolation from these large domestic animals to humans is problematic, as is the more frequent extrapolation from rodents to humans. It can be concluded that longterm exposure to low levels of cadmium is associated with impaired reproduction in dairy cows.

Research in 1984 indicated that the cadmium body burden was higher in a village where the soil is contaminated with cadmium (Luyksgestel) than in a control village (Zeeland). The distribution of kidney function parameters also differed between the two villages. The aim of this study is to estimate the lifetime accumulated cadmium intake from food for the people from both villages. Various data sets describing dietary patterns in the Netherlands were used. The assessed average lifetime accumulated cadmium intake from food by the study subjects (aged 30-69 years) was 435 mg (+/- 131 mg) in Luyksgestel and 394 (+/- 113 mg) in Zeeland. The estimated lifetime accumulated cadmium intake for a hypothetical allotment gardener of 55 years was 520 mg from vegetables grown on uncontaminated soil, and 655 mg for lifelong consumption of vegetables from contaminated soil. The Luyksgestel subjects' estimated cadmium intake from food was well below the provisional tolerable weekly intake as proposed by the WHO, of 400-500 micrograms or 1124-1404 mg for the lifelong intake by a 55-year-old man.

The border region between Belgium and The Netherlands, the Kempen, was found to be polluted with cadmium. The main route of pollution had been by air but some cadmium came by way of surface-water and solid waste. This resulted in an increase in the cadmium content of locally grown vegetables. The consequential exposure to cadmium of humans living in the area has been estimated using various methods and is approximately the FAO/WHO maximum allowable daily intake, smoking disregarded. Several studies of possible effects on public health were conducted. Among these studies were two geographic studies, one on hospital admissions for various non-malignant diseases and one on cancer-incidence. Two cohort studies on possible teratogenic effects in a non-occupationally exposed, non-smoking vegetarian population with a high fertility and good registration were also conducted. A survey on cadmium content of the urine and kidney damage in a longtime but non-occupationally exposed rural population and a reference population formed the main study. Also, a survey on cadmium content of the kidney samples of autopsied patients in a population based study and a reference population was conducted. Together these studies showed that the extra exposure had lead to an additional body-burden of cadmium resulting in various signs of malfunction. In consequence of the findings the Netherlands Ministry for Housing, Physical Planning and Environment appropriated money to cleanup contaminated gardens.