Silicic acid, lead salt

Short-term toxicity to aquatic invertebrates

Administrative data

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

migrated information: read-across based on grouping of substances (category approach)

Adequacy of study:

weight of evidence

Study period:

February 2010

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Guideline followed. Study well conducted.

Data source

Reference

Reference 1

Reference Type:

study report

Title:

Unnamed

Year:

2007

Reference 2

Reference Type:

study report

Title:

Unnamed

Year:

2010

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

other: USEPA(2002) Methods for measuring the acute toxicity of effluents and receiving waters to freshwater organisms. Cincinnati, Ohio, U.S. Environmental Protection Agency

GLP compliance:

no

Test material

Test material information

Constituent 1

Reference substance name:

Lead dinitrate

EC Number:

233-245-9

EC Name:

Lead dinitrate

Cas Number:

10099-74-8

Details on test material:

- Name of test material (as cited in study report): Pb

Sampling and analysis

Analytical monitoring:

yes

Test solutions

Vehicle:

no

Test organisms

Test organisms (species):

Ceriodaphnia dubia

Details on test organisms:

- Test organisms originate from Aquatic Biosystems and maintained in dechlorinated tapwater at 26°C
- For all tests, a mass culture was started and maintained for 3 days. All mass cultures were fed with a combination of YCT and algae
- Test organisms were < 24 h old before testing

Study design

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Test conditions

Hardness:

5.8 mg/L See for details the table below.

Test temperature:

25°C
See for details the table below.

pH:

5.71See for details the table below.

Nominal and measured concentrations:

pH Nominal Pb (µg/L) Measured Pb (µg/L)
5.71 0, 5, 10, 20, 40, 80 0, 3, 9, 17, 36, 76
6.78 0, 25, 75, 150, 300, 600 1, 18, 52, 127, 271, 569
7.18 0, 250, 350, 500, 700, 1000 0, 282, 371, 596, 820, 1161
7.27 0, 100, 200, 400, 800, 1600 0, 41, 100.7, 241.0, 746, 1740.8
7.32 0, 1000,2000, 3000, 4000, 5000 3, 985, 2153, 2879, 4030,5911
7.43 0, 300, 400, 500, 600, 700 0, 157, 256, 315, 421, 440
7.44(H=121.8) 0, 400, 800, 1200, 1600, 2000 0, 261, 641, 1096, 1386, 1707
7.44 0, 400, 800, 1200, 1600, 2000 0, 355, 723, 1097, 1584, 1851
7.48 0, 50, 150, 300, 600, 1000 0, 345, 704, 1019, 1379, 1732
7.49 0, 300, 600, 900, 1200, 1500 0, 203, 615, 1069, 1398, 1569
7.58 0, 200, 350, 500, 650, 800 0, 180, 373, 477, 575, 907
7.8 (H=40.5) 0, 200, 400, 600, 800, 1000 0, 219, 483, 819, 1004, 1303
7.8 0, 400, 600, 800, 1000, 1200 0, 491, 801, 1129, 1481, 1695
7.89 0, 200, 400, 600, 800, 1000 0, 101, 236, 404, 566, 802
7.96 0, 400, 800, 1200, 1600, 2000 0, 279, 504, 921, 1236, 1344
8.06 0, 300, 600, 900, 1200, 1500 0, 389, 798, 1152, 1576, 1876
8.15 0, 200, 400, 600, 800, 1000 0, 345, 704, 1019, 1379, 1732
8.15(H=103.2) 0, 400, 1200, 2000, 3500, 6000 0, 271, 888, 1571, 3039, 5026
8.2 0, 400, 800, 1000, 1200, 1600 0, 416, 772, 1081, 1164, 1547
8.23 0, 300, 600, 900, 1200, 1500 0, 355, 742, 1102, 1518, 1890
8.36 0, 50, 100, 200, 400, 800, 1600, 3200, 6400 2, 35, 72, 170, 91, 120, 227, 186, 182
8.58 0, 500, 1000, 2000, 4000, 8000 1, 378, 1039, 1722, 3048, 6369

Details on test conditions:

- 5 individuals/20 mL polyethylene cups
- 4 replicates were used for testing

Results and discussion

Effect concentrations

Duration:

48 h

Dose descriptor:

LC50

Effect conc.:

>= 28.8 - <= 3 115.8 µg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

dissolved

Basis for effect:

mortality

Remarks on result:

other: 5.71

Reported statistics and error estimates:

All acute tests were assessed for LC50 values using Maximum Likelihood Probit or Trimmed Spearman Karber method

Any other information on results incl. tables

LC values compared to the various water parameters:

pH	Hardness	Na^+	K^+	Ca^2+	Mg^2+	Cl^-	SO4^2-	CO2	DOC	48h-LC50 (µg/L)
6.78	5.8	81	60	32	26	72	19	n.d.	104	28.8
5.71	16.4	78	55	106	58	408	21	n.d.	50	73.56
7.27	38.1	640	65	295	86	767	71		216	100.12
8.36	227.8	1475	181	1152	1126	936	492	n.d.	137	107.7
7.18	15.7	108	47	99	58	115	20	n.d.	622	290.33
7.43	244.4	1411	67	2302	142	1078	1528	555	321	318.74
7.96	50.4	2168	74.3	400	104	1385	133	857	214	383.79
7.58	46.1	1260	64.4	315	146	1063	85	506	213	394.78
7.8	40.5	1179	58.3	256	149	887	63	714	228	424.76
7.44	74.4	735	49.7	614	130	1110	90	587	242	432.77
7.48	32.1	2164	59.3	216	106	2066	119	428	216	446.43
7.89	99.7	2477	110	701	297	2198	204	n.d.	415	531.9
7.8	53.1	1216	66	361	170	1012	75	793	266	547.47
8.06	43.7	2937	69.3	295	142	1445	108	1715	228	571.28
7.49	35.5	1256	54.8	221	134	861	63	621	171	590.94
7.44	121.8	792	51.4	1088	130	1110	90	587	242	596.83
8.23	39.4	2944	58.4	289	105	928	70	2175	199	764.73
8.2	50	2823	74.4	396	104	1485	96	1326	233	779.17
8.15	97.3	2535	110	673	302	2152	215	n.d.	897	963.9
8.58	225.5	401	58	2157	98	393	3824	n.d.	653	995.7
7.32	27.8	230	87	218	60	250	25	n.d.	1467	1179.6
8.15	103.2	4034	282	796	242	3391	368	n.d.	1298	3115.8

Applicant's summary and conclusion

Conclusions:

Increasing DOC or pH decreases the toxicity of lead in invertebrates significantly due to a decrease of the bioavailability of the lead ion. Changing the hardness or concentrations of Na+, K+ or Mg2+ had no additional significant effect on toxicity expressed as the 96h-LC50 for C. dubia. The lowest and the highest 48h-LC50 differed by three orders of magnitude (range: 30 - 3100 µg/L).

Executive summary:

In a study according to guideline US EPA (2002), 22 individual reliable acute toxicity data points for one specie Ceriodaphnia dubia were summarized in this data point:

After exposures were conducted under static conditions and for different pH and hardness values, the acute toxicity values (48h-LC50) for Ceriodaphnia dubia varied between 28.8 µg dissolved Pb/L (at pH 6.8, a DOC of 104 mg/L and hardness of 5.8 mg CaCo3/L) and 3115.8 µg dissolved Pb/L (at pH 8.15, a DOC of 1298 mg/L and hardness of 103.2 mg/L).