• Meeting
• Appeal
• History of S&E
• Symposia organised by S&E
• Publications resulting from S&E activities

Meetings of the Netherlands Working Group on Statistics and Ecotoxicology.

In June 2005 the working group S&E will arrange a meeting.

The subject of this afternoon will be "Common statistics problems in standard ecotoxicology". The topic will be introduced in the presentation:

1. Nelly van der Hoeven (ECOSTAT): Statistics in chronic fish tests.

For information on this meeting, please contact Nelly van der Hoeven,

Generally, the meetings of the working group Statistics and Ecotoxicology are in Dutch. On special request of a participant, the English language may be used. Please, present such a request beforehand.

Information on past meetings

On November 4th, 2004 the working group had a meeting. On this meeting, two presentations were given:

1. Tjalling Jager (VUA) has discussed the analysis of survival data with DEBtox; about dose-response, thresholds and receptors.
2. Tom Aldenberg (RIVM) has discussed predictive uncertainty of QSAR regression models.

For information on this meeting mail to Nelly van der Hoeven,

On march 14th, 2004 the working group had a meeting. On this meeting, two presentations were given:

1. Tjalling Jager (VUA) has discussed the dose-response relation in the debTOX model.
2. Theo Traas and Etje Hulzebos (both RIVM) had discussed Cross validation versus external validation in QSAR models.

For information on this meeting mail to Nelly van der Hoeven,

On October 30th, 2003 the working group had a meeting. On this meeting, two presentations were given:

1. Tjalling Jager (VUA) has introduced and discussed the DebTox model.
2. Mathijs Smit (TNO-MEP) has presented the TNO research on SSDs and PEC/PNEC relations.

For information on this meeting mail to Nelly van der Hoeven,

On March 27th, 2003 the working group had a meeting. The main topic of this afternoon was the measurement of bacterial toxicant tolerance using microtiter plates.
At the meeting the following presentations were given:

1. Description of the methods
2. Data reduction by filtering white noise
3. The use of sensitivity distributions to determine the NOEC and the PAF

On October 10th, 2002 the working group had a meeting. The main topic of this afternoon was statistics in combination toxicology. At the meeting the following presentations were given:

1. Combitox. Research on soil organisms: Fundamentals, methods and preliminary results.
   Kees van Gestel (VUA)
2. About quantifying mixture toxicity data. Predicting combined effects: mission impossible.
   Martijs Jonker (WU)

On march 14th, 2002 the working group had a meeting. At that meeting the following presentations were given:

1. SSDs, statistics, ecology, toxicology and something else????
   Leo Posthuma (RIVM)
2. The use of probabilistic techniques in ecological risk assessment of pesticides. A report on two international workshops.
   Paul van den Brink (Alterra)
3. In the algal growth-inhibition test several parameters can be estimated. Can any of them be chosen on statistical considerations?
   Rinus Bogers (NOTOX)

On september 13th, 2001 the working group had a meeting. At that meeting the following presentations were given:

1. The problem of incomplete and non-random data and its consequences for slope estimation in quantal regression.
   Wout Slob (RIVM)
2. Correction for measurement error in variance estimation.
   Wout Slob (RIVM)
3. SSD (Species Sensitivity Distribution) with uncertainty in the data: 3e order Monte Carlo?
   Tom Aldenberg (RIVM)
   

On february 15th, 2001 the working group had a meeting. At that meeting the following presentations were given:

1. The use of species sensitivity distributions in setting quality standards and risk-analysis: new developments
   (In dutch: Het gebruik van soortgevoeligheidsverdelingen in normstelling en risico-analyse: nieuwe ontwikkelingen).
   Theo Traas en Tom Aldenberg (beide RIVM)
2. An alternative for NOEC tests: Does the effect on survival remains below some acceptable level?
   (In dutch: Alternatief voor NOEC toetsen: Blijft een effect op sterfte beneden een aanvaardbaar niveau?).
   Nelly van der Hoeven (ECOSTAT)

For information on this meeting mail to Nelly van der Hoeven,

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Appeal to those interested in
the Netherlands Working Group on Statistics and Ecotoxicology

Dear sympathizers,

The Netherlands Working Group on Statistics and Ecotoxicology (S&E) is active in all statistical aspects of analysing, developing and interpreting ecotoxicological research. S&E is a working group of the Biometrical section of the Netherlands Society of Statistics (VVS), and of the Environmental Toxicology section of the Netherlands Society of Toxicology.

About twice a year, S&E organizes a meeting. In these meetings, a member introduces some problem on the border between statistics and ecotoxicology. After the introduction, the problem will be discussed in the meeting, trying to find the right approach. All S&E-members in the meeting participate actively in that discussion.

In ecotoxicology many statistical questions are still open. For instance, power analysis of ecotoxicological experiments, methods to estimate the EC50 and ECx, the introduction of the DEBtox model, the use of probabilistic techniques and methods to correct for background properties of natural materials in ecotoxicological research.

Are you interested in any of these subjects or in some other statistical aspect of ecotoxicology, do not hesitate to contact us.
Mail to Nelly van der Hoeven, .
Note however, that unless requested beforehand, the meetings of the our working group will be in Dutch.

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History of the Netherlands Working Group on Statistics and Ecotoxicology.

The Netherlands Institute for Standardization, NNI, was running working groups on the standardization of several ecotoxicological tests. At the end of the eighties, the members of these working groups discoverd that they all run into the same statistical questions. They decided to start a separate working group to tackle the statistics of ecotoxicological tests.

In this working group, statistically interested ecotoxicologists and ecotoxicologically interested statisticians met. Soon, the field of the working group was extended to statistics in all kind of ecotoxicological research. Twice, the working group has organized a symposium to make their ideas known to a wider circle. These symposia let to several
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Symposia organised by the Working Group on Statistics and Ecotoxicology.

In September 1994 S&E has organized the workshop 'How to measure no effect'. This workshop was organized in cooperation with the Risk Assessment and Environmental Quality Division of the Netherlands Ministry of Housing, Spatial Planning and the Environment (VROM). The results of this workshop are published.

In November 1997 S&E has organized a one day symposium 'Statistics in Ecotoxicology'. This symposium was held at the Free University of Amsterdam. In this symposium, several activities of S&E were presented.

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Publications resulting from activities of the working group on Statistics and Ecotoxicology.

Hoeven, N. van der, 2004
Current Issues in Statistics and Models for Ecotoxicological Risk Assessment.
Acta Biotheoretica 52: 201 - 217

Hoeven, N. van der, 1998
Power analysis for the NOEC: What is the probability to detect small toxic effects on three different species using the appropriate standardized test protocols?
Ecotoxicology 7: 355-361

Hoeven, N. van der, J. Schobben, F. Noppert & J. Bedaux, 1997
Report on the one day symposium Statistics in Ecotoxicology, November 4, 1997 (In Dutch: Verslag van het minisymposium Statistiek in de Ecotoxicologie, 4 november 1997
TCCD 20, nr 4: 13-14

Hoeven, N. van der, F. Noppert & A. Leopold, 1997
How to measure no effect? Part I: Towards a new measure of chronic toxicity in ecotoxicity. Introduction and workshop results.
Environmetrics 8: 241-248

Straalen, N.M. van, 1997
How to measure no effect, part II: Threshold effects in Ecotoxicology.
Environmetrics 8: 249-253

Hoeven, N. van der, 1997
How to measure no effect? Part III: Statistical aspects of NOEC, ECx and NEC estimates.
Environmetrics 8: 255-261

Bruijn, J.H.M. de & Hof, M., 1997
How to measure no effect, part IV: How acceptable is the ECx from an environmental policy point of view?
Environmetrics 8: 263-267

Straalen,. N.M., N. van der Hoeven, J. de Bruijn & M. Hof, 1994
How to measure no effect.
Workshop report. The Netherlands Working Group on Statistics and Ecotoxicology.

Hoekstra, J.A. & P. van Ewijk, 1993
Alternatives for the No-Observed-Effect Level
Environmental and Toxicological Chemistry 12, 187-194

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