Exposure response function for nitrate and iMetHb: Difference between revisions

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Scope

To define the exposure response factor for nitrate exposure from drinking water causing iMetHb

European countries
Infants < 6 months of age
Oral exposure from drinking water via baby food formula or drinking water.

Definition

Causality

NA

Data

Accoding to US EPA IRIS (Integrated Risk Information System) NOAEL for nitrate is 10 mg nitrate-nitrogen/L (1.6 mg/kg/day) and LOAEL is 11-20 mg nitrate-nitrogen/L (1.8-3.2 mg/kg/day). Conversion Factor for nitrate-nitrogen is expressed as the amount of nitrogen within the nitrite molecule commonly shown as mg nitrate-nitrogen/L (1 mg nitrate-nitrogen = 4.4 mg nitrate. The oral Reference Dose (RfD), which is based on the assumption that thresholds exist for certain toxic effects such as cellular necrosis, is 1.6E+0 mg/kg/day. This results in early clinical signs of methemoglobinemia in excess of 10% (0-3 months old infants formula). U.S. EPA has evaluated the noncancer oral data for nitrate and derived a reference dose (RfD) of 1.6 mg/kg-day with 10 % of risk to MetHb.

http://www.epa.gov/NCEA/iris/subst/0076.htm

Formula

Unit

mg/kg/d / mg/l

Result

Slope of exposure response function for nitrate and iMet Hb= 0.06585
Environmental risk level for NO3- =133.7 mg/l
No observed adverded effect level (NOEL) for nitrate in drinking water= 1.6 mg/kg/d
LOAEL for NO3- = 15,5 mg/l
US EPA reference oral dose for nitrate = 7 mg/kg/d
Acceptable daily intake of NO3- = 3.7 mg/kg/d

@@ Line 2: / Line 2: @@
 == Scope<br> ==
+To define the exposure response factor for nitrate exposure from drinking water causing iMetHb
 *European countries
@@ Line 10: / Line 11: @@
 == Definition<br> ==
-Exposure response factor for nitrate exposure from drinking water causing iMetHb.<br>
 === Causality<br> ===
+NA
 === Data<br> ===
-Accoding to US EPA IRIS (Integrated Risk Information System) NOAEL for nitrate is 10 mg nitrate-nitrogen/L (1.6 mg/kg/day) and LOAEL is 11-20 mg nitrate-nitrogen/L (1.8-3.2 mg/kg/day). Conversion Factor for nitrate-nitrogen is expressed as the amount of nitrogen within the nitrite molecule commonly shown as mg nitrate-nitrogen/L (1 mg nitrate-nitrogen = 4.4 mg nitrate. The oral Reference Dose (RfD), which is based on the assumption that thresholds exist for certain toxic effects such as cellular necrosis, is 1.6E+0 mg/kg/day. This results in early clinical signs of methemoglobinemia in excess of 10% (0-3 months old infants formula). This results in exposure response factor:
+Accoding to US EPA IRIS (Integrated Risk Information System) NOAEL for nitrate is 10 mg nitrate-nitrogen/L (1.6 mg/kg/day) and LOAEL is 11-20 mg nitrate-nitrogen/L (1.8-3.2 mg/kg/day). Conversion Factor for nitrate-nitrogen is expressed as the amount of nitrogen within the nitrite molecule commonly shown as mg nitrate-nitrogen/L (1 mg nitrate-nitrogen = 4.4 mg nitrate. The oral Reference Dose (RfD), which is based on the assumption that thresholds exist for certain toxic effects such as cellular necrosis, is 1.6E+0 mg/kg/day. This results in early clinical signs of methemoglobinemia in excess of 10% (0-3 months old infants formula). U.S. EPA has evaluated the noncancer oral data for nitrate and derived a reference dose (RfD) of 1.6 mg/kg-day with 10 % of risk to MetHb.
 http://www.epa.gov/NCEA/iris/subst/0076.htm
@@ Line 25: / Line 23: @@
 === Formula<br> ===
 === Unit<br> ===
+mg/kg/d / mg/l
 == Result<br> ==
-If possible, a numerical expression or distribution.<br>
+*Slope of exposure response function for nitrate and iMet Hb= 0.06585
+*Environmental risk level for NO3- =133.7 mg/l
+*No observed adverded effect level (NOEL) for nitrate in drinking water= 1.6 mg/kg/d
+*LOAEL for NO3- = 15,5 mg/l
+*US EPA reference oral dose for nitrate = 7 mg/kg/d
+*Acceptable daily intake of NO3- = 3.7 mg/kg/d