Your levels are perfectly normal if the figures you reported are accurate. Nickel and chromium don't usually accumulate in the body despite the fact that they are present in soil, water, and many foods.

For this reason, "normal" levels are very low. That's why these nutrients are usually referred to as "trace" minerals. Normal values are set at 0.3 ng/mL for nickel (upper limit is 1.1 ng/L) and 0.15 ng/mL for chromium (levels vary in people from different parts of the world).

Scientists are researching the effect of metal implants on blood levels of these trace minerals. There may be some long-term effects but not enough information is availble yet to say for sure.