Answer Parts D & E:

Atrazine is a popular herbicide, tens of millions of pounds of atrazine are applied to vegetation in the U$.$S$.$ annually and is a widespread drinking water contaminant. $($a$)$ What are the NOAEL and RfD for atrazine, and to which response do these doses refer? $($b$)$ Assume the following additional toxicity data points: LOAEL $5$ mg$/$kg$/$day $($affects $5\%$ of population$)$; LD$5015$ mg$/$kg$/$day; Other data points $22$ mg$/$kg$/$day $($affects $75\%$ of population$),30$ mg$/$kg$/$day $($affects $95\%$ of population$).$ Draw a dose$-$response curve for these data. $($c$)$ What is the approximate slope of the curve?

$($d$)$ Now consider applying atrazine to your lawn and assume that there are babies in the household that like to eat grass. What is the maximum amount of grass that a baby can eat safely in a day? Assume the following conditions: baby weight ~$10$kg$,$ residual atrazine concentration on grass from one application is ~$0\mathrm{.}01\%($where $1\%=10,000$ ppmm$).$

$($e$)$ Given these results from part $($d$),$ does spraying your lawn with atrazine present any serious risk in this case? Use the $$Hazard Quotient$$ to make this determination.