Target organ toxicity INDEX

Target Organ Toxicity Dose (TTD) A variant of the hazard index approach where effects for all components for all affected tissues. The target organ toxicity dose is summed regardless of whether they represent the critical effect or a secondary effect. Hazard index values are developed for each affected organ or system. 

The ratio referred to in the third step is utilized to quantify risk from noncarcinogens. As the fourth step indicates, the hazard index for individual chemicals may be summed for chemicals affecting a particular target organ or acting by a common mechanism in order to provide a final measure of noncarcinogenic toxic risk. If the sum of hazard indices is less than one, then the risk of adverse health effects is considered acceptable. 

Certainly, most in vitro assays cannot predict (a) metabolite effects, (b) adverse effects associated by accumulation, and (c) drug actions at targets with mutations. Nevertheless, early safety-profiling assays have the power to detect trends toward certain adverse reactions and organ toxicity and to navigate drug discovery teams away from them. The major difficulty is estimating the impact of the data on the clinical performance determined by the human therapeutic index. 

Properties Colorless to pale yel. liq. sol. in alcohol, acetone, esters, hydrocarbons, most org. solvs. si. sol. in water m.w. 152.21 dens. 1.030 b.p. 153 C flash pt. 175 F ref. index 1.5210 Toxicology LD50 (oral, rat) 382 mg/kg, (IP, mouse) 270 mg/kg, (skin, rat) 95 mg/kg poison by ing. and IP routes mod. toxic by inhalation and skin absorption readily absorbed thru skin experimental tumorigen mutagenic data skin and eye irritant target organs liver, kidneys TSCA listed... 

Properties Clear pale yel. liq. or solid sol. in ketones, esters, acetone, benzene, aromatic soivs. insol. in water, alcohol m.w. 631.56 dens. 1.066 m.p. 23 C f.p. 8 C flash pt. 440 F ref. index 1.4710 Toxicology ACGIH TLV/TWA0.1 mg(Sn)/m (skin) ED50 (oral, rat), 3954 mg/kg, (dermal, rabbit) > 2000 mg/kg EDEo (IP, rat) 85 mg/kg toxic poison by ing. and IP routes conosive skin/eye irritant readily absorbed thm skin target organs Gl system, nerves, liver TSCA listed Precaution Combustible reacts with oxidizers Hazardous Decomp. Prods. Heated to decomp., emits acrid smoke and fumes... 

C autoignition temp. 475 C ref. index 1.515-1.518 surf. tens. 35 dynes/cm dielec, const. 4.33 Toxicology LD50 (oral, rat) 3700 mg/kg LC50 (inh., mouse, 2 h) 3021 mg/m mod. toxic by ing. and inh. skin irritant target organs CNS, respiratory system TSCA listed... 

Dimethyl diketone. See Diacetyl Dimethyidimethoxysilane CAS 1112-39-6 EINECS/ELINCS 214-189-4 Synonyms Dimethoxydimethylsilane Silane, dimethoxydimethyl-Empin cal C4Hi202Si Formula (CH3)2Si(CH30)2 Properties Liq. m.w. 120.2 dens. 0.864 b.p. 82 C flash pt. -8 C ref. index 1.3708 Toxicology Toxic by inh., ing., skin contact irritating to eyes, skin, respiratory system harmful by ing., inh., skin absorp. may cause drowsiness target organs eyes, kidneys ... 

Properties Colorless, cryst. solid m.w. 86.38 dens.. 816 dec. on warming ref. index 1.3381 Toxicology Corrosive toxic target organ eyes, kidneys TSCA listed Precaution Flammable liq. 

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