Major objective of a toxicological study is to quantify the effects of the suspect

toxicant on a target organism. Point out and briefly explain $5$ important items to be

identified before undertaking the toxicological study.

A pilot plant was recently opened to produce benzene and toluene from petroleum and

natural gas condensate. According to the technical report, this production operation

evaporates $2n\frac{t}{h}$ of toluene and $1$ pint per $8h$ shift of benzene. Calculate the ventilation

rate required to maintain the vapor concentration below the TLV; where,

$TL{V}_{\text{b}\text{e}\text{n}\text{z}\text{e}\text{n}\text{e}}=10ppm$ and $TL{V}_{\text{t}\text{o}\text{l}\text{u}\text{e}\text{n}\text{e}}=50ppm.$ The temperature is $80F$ and the pressure is

$1$atm. Assume the water density of $62\mathrm{.}4lb\frac{m}{f}{t}^3$ and non$-$ideal mixing factor, $k$ of $0\mathrm{.}1.$

Specific gravity of toluene and benzene $=0\mathrm{.}866$ and $0\mathrm{.}879$ ; Molecular weight of toluene

and benzene $=78\mathrm{.}11lb\frac{m}{l}b-$mol and $92\mathrm{.}14lb\frac{m}{l}b-$mol