That is always going to depend on the context. Sometimes a small number makes a difference, sometimes not.
40 times greater chance of a comet hitting you on the head? Still gonna be negligible and you probably shouldn't be too concerned.
40 times more lead in your eggs? Well, you should really be aiming for zero lead in your eggs and lead poisoning can happen over time (My cousins got lead poisoning from old plates and bowls). If you have chickens, you are probably being fed a consistent diet of eggs. So yeah, it might very well be a concern.
You didn't answer the question, you just reiterated that lead is bad.
Is this 40x the chance of getting hit by a comet, or 40 games of Russian roulette.
The study talks about increased blood lead levels ~1 to 1.4 μg/dL. Now how risky is that? The CDC has alert levels for children of 5 ug/dL, recently revised from 10 ug/uL.
What the measurable impact is from 5ug, let alone 1 ug is hotly debated because it is so difficult to asses.
Here is the study they cross reference:
>Our IEUBK model predictions suggested that consuming one egg per day with a lead concentration less than 100 μg/kg, in addition to the model’s default lead exposure from diet and all other sources, would result in estimated GM blood-lead concentration increases of less than 1 μg/dL in children. However, daily consumption of one egg with the highest lead concentration we found in eggs from NYC community gardens (167 μg/kg) would increase GM blood-lead concentrations by 1 to 1.4 μg/dL, and daily consumption of one egg with 300 μg/kg lead would increase GM blood-lead concentrations by as much as 2.4 μg/dL, well above the 1 μg/dL guideline.
The IEUBK model output was also used to estimate the number of eggs children could consume without excessively increasing blood-lead concentrations. Among children 1 – 6 years of age, the model output suggested that an increase in dietary lead intake of up to 5.6 μg/day for 1 to 2 year olds (and slightly larger increases – as much as 7.6 μg/day – for older children), would raise GM blood-lead concentrations by less than 1 μg/dL. This intake translates into the consumption of about 6 medium eggs/day at 20 μg/kg lead, 2.5 eggs/day at 50 μg/kg, or 1.2 eggs/day at 100 μg/kg.
These evaluations implied that, overall, the lead concentrations we found in eggs from NYC community gardens were not likely to significantly increase lead exposure or to pose a significant health risk. However, frequent consumption of eggs with the highest lead concentration we found could significantly increase lead exposure, and chickens exposed to higher concentrations of lead in soil are likely to produce eggs with higher concentrations of lead. This exposure pathway could potentially be significant in some gardens, and it should not be ignored
40 times greater chance of a comet hitting you on the head? Still gonna be negligible and you probably shouldn't be too concerned.
40 times more lead in your eggs? Well, you should really be aiming for zero lead in your eggs and lead poisoning can happen over time (My cousins got lead poisoning from old plates and bowls). If you have chickens, you are probably being fed a consistent diet of eggs. So yeah, it might very well be a concern.