Dipotassium oxide

Monitoring data

Administrative data

Endpoint:

monitoring data

Type of information:

other: Published handbook data

Adequacy of study:

weight of evidence

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

comparable to guideline study

Justification for type of information:

Klimisch score based on test procedure being in accordance with generally accepted scientific standards and described in sufficient detail (according to OECD SIDS document for potassium hydroxide, 30 January 2002). Potassium oxide is a basic oxide and reacts with water violently to produce the caustic potassium hydroxide When water is added to Potassium oxide, KOH is produced. K2O+H2O→KOH Therefore, the health effects of Potassium Hydroxide need to be considered in the assessment of Potassium oxide.

Data source

Reference

Reference Type:

publication

Title:

Water quality of world river bassins

Author:

UNEP

Year:

1995

Bibliographic source:

UNEP Environment Library N°14, Nairobi, Kenya

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

other: OECD SIDS document for potassium hydroxide, 30 January 2002).

Principles of method if other than guideline:

test procedure being in accordance with generally accepted scientific standards and described in sufficient detail (according to OECD SIDS document for potassium hydroxide, 30 January 2002).

GLP compliance:

not specified

Type of measurement:

background concentration

Media:

surface water

Test material

Test material information

Constituent 1

Reference substance name:

Potassium hydroxide

EC Number:

215-181-3

EC Name:

Potassium hydroxide

Cas Number:

1310-58-3

Molecular formula:

HKO

IUPAC Name:

potassium hydroxide

Test material form:

solid: compact

Details on test material:

Potassium oxide is a basic oxide and reacts with water violently to produce the caustic potassium hydroxideWhen water is added to Potassium oxide, KOH is produced.K2O+H2O→KOH Therefore, the health effects of Potassium Hydroxide need to be considered in the assessment of Potassium oxide.

Results and discussion

Concentration

Concentration 1

Country:

other: 75 world rivers (average concentration)

Substance or metabolite:

other: Potassium

Conc.:

3.22 mg/L

Remarks on result:

other: 10th percentile: 0.80 mg/l, 90th percentile: 5.96 mg/l, range 41.90 mg/l

Concentration 2

Country:

other: 75 world rivers (average concentration)

Substance or metabolite:

other: pH

Conc.:

> 6.5 - < 8.3 mg/L

Remarks on result:

other: global median pH = 7.7

Concentration 3

Country:

other: 11 rivers from North America (average concentration)

Substance or metabolite:

other: Potassium

Conc.:

2.35 mg/L

Remarks on result:

other: 10th percentile: 0.80 mg/l, 90th percentile: 5.00 mg/l, range 7.20 mg/l

Concentration 4

Country:

other: 25 rivers from Asia (average concentration)

Substance or metabolite:

other: Potassium

Conc.:

2.17 mg/L

Remarks on result:

other: 10th percentile: 0.84 mg/l, 90th percentile: 3.94 mg/l, range 6.80 mg/l

Concentration 5

Country:

other: 5 rivers from South America (average concentration)

Substance or metabolite:

other: Potassium

Conc.:

1.58 mg/L

Remarks on result:

other: 10th percentile: 0.74 mg/l, 90th percentile: 2.30 mg/l, range 1.8 mg/l

Concentration 6

Country:

other: 7 rivers from Africa (average concentration)

Substance or metabolite:

other: Potassium

Conc.:

1.84 mg/L

Remarks on result:

other: 10th percentile: 1.16 mg/l, 90th percentile: 2.66 mg/l, range 2.10 mg/l

Concentration 7

Country:

other: 23 rivers from Europe (average concentration)

Substance or metabolite:

other: Potassium

Conc.:

5.88 mg/L

Remarks on result:

other: 10th percentile: 0.80 mg/l, 90th percentile: 7.00 mg/l, range 41.40 mg/l

Concentration 8

Country:

other: 6 rivers from Oceania (average concentration)

Substance or metabolite:

other: Potassium

Conc.:

2.87 mg/L

Remarks on result:

other: 10th percentile: 0.40 mg/l, 90th percentile: 5.00 mg/l, range 5.60 mg/l

Details on results:

Levels of concern for water quality from anthropogenic exposure, predominantly fertilizers, are never reached (12 mg/l WHO guideline for drinking water), except downstream from potash mines (Weser: 42.0 mg/l; Elbe: 26.1 mg/l). Acidity/alkalinity is measured as pH which is a key parameter in water quality. pH is closely linked to biological productivity in aquatic systems. With dissolved organic acids from soil leaching (Amazonia), a pH of less than 4.0 has been measured. In waters with a high chlorophyll content, the bicarbonate assimilation can result in pH values exceeding quiet commonly 8.5, and even 9.0 at midday (Loire)

Applicant's summary and conclusion

Conclusions:

Average Potassium concentration worldwide is 3.22 mg/L, averge in Europe is 5.88 mg/L, Potassium concentration is above 12 mg/l downstream of potash mines. Monitoring values worldwide. pH annual average 6.5 - 8.3; global median value 7.7. No strong variability at individual stations.
Potassium oxide is a basic oxide and reacts with water violently to produce the caustic potassium hydroxide
When water is added to Potassium oxide, KOH is produced.
K2O+H2O→KOH
Therefore, the health effects of Potassium Hydroxide need to be considered in the assessment of Potassium oxide.