Blog: Occupational Hygiene Insights on DOHSBase

Your substance list, kept up to date automatically: shortlist, change alerts and CSV export

Tue, 29 Sep 2026 00:00:00 +0000

In brief: In DOHSBase Online you build a shortlist of the substances you work with. Turn on substance change alerts and you receive a daily email as soon as a limit value or hazard classification of one of those substances changes, with the old value shown next to the new one for each substance. Export to CSV takes the list into a spreadsheet. This post first appeared as the DOHSBase newsletter for September 2026.

Farewell to dohsbaseonline.com: seven years, and now one portal

Mon, 27 Jul 2026 00:00:00 +0000

Today we switched off the old DOHSBase portal at dohsbaseonline.com. After seven years, from 2019 until now, that address is no longer a separate application. Anyone who still goes there lands automatically on the new portal: portal.dohsbase.nl. From now on, that is the only portal.

In brief: The portal that ran on dohsbaseonline.com since 2019 has been retired. Existing links and bookmarks to dohsbaseonline.com keep working — they redirect automatically (301) to portal.dohsbase.nl, so you don’t need to change anything. The new portal is not just a move: it has been rebuilt, and we have already shipped a series of improvements since launch.

Belgian limit values in DOHSBase: the Codex list, the CMR scope and the new BE profile

Tue, 21 Jul 2026 00:00:00 +0000

DOHSBase now includes the Belgian occupational exposure limits from the Codex on well-being at work. The values are part of the limit-value data and the associated CMR classification has been processed into the CMR data. There is also a separate BE profile, in which Belgium rather than the Netherlands is the starting point.

One distinction up front: the Belgian data is not confined to that BE profile. It has also been added to the other European profiles, so if you work with a Dutch or European profile you will see the Belgian value listed from now on as well.

CMR classification at a glance: every source on one screen

Sun, 21 Jun 2026 00:00:00 +0000

Determining a substance’s CMR status often takes more time than it should. The information is scattered across different lists and sources: the harmonised EU classification (CLH), the SZW CMR list, IARC, ACGIH, the Health Council and manufacturers’ self-classifications. None of them is complete on its own. To make that assessment easier, DOHSBase Online now brings these sources together in a single overview on the hazard classification tab. At a glance you see whether a substance is carcinogenic, mutagenic or reprotoxic, which sources say so, and how certain that classification is.

DOHSBase Compare rebuilt: substance ranking in DOHSBase Online

Thu, 07 May 2026 00:00:00 +0000

DOHSBase Compare is back. What started in the early 2000s as the Vergelijk mode in the offline desktop version of DOHSBase2000 — a tool that let occupational hygienists rank a list of substances by health risk — has now been fully reimplemented in DOHSBase Online. The calculation core remains the TOX × TIX = RAS methodology of Wieling and Scheffers (NVvA Newsletter 2006-01); the web build brings that methodology into a shared, browser-based workflow for the first time.

White Spirit OELV: Application to Complex Hydrocarbon Mixtures

Tue, 28 Apr 2026 00:00:00 +0000

Through SCOEL SUM/087, the EU’s Scientific Committee on Occupational Exposure Limits recommended an OELV (Occupational Exposure Limit Value, per EN 689) for white spirit — also known as Stoddard solvent or mineral spirits — of 116 mg/m³ (8-hour TWA) and 290 mg/m³ (15-min STEL). At EU level, no binding BOELV or indicative IOELV has been set for white spirit; SUM/087 is SCOEL’s recommendation, used as the EU-level reference in practice. SCOEL also explicitly defines the scope of that OELV as covering all complex C6–C12 hydrocarbon mixtures — not just the four white spirits SCOEL lists (Types 1, 2 and 3, including Stoddard solvent), all of which are now in EU commercial use. That broad applicability is the core of how the OELV is used, with one critical guardrail: components with a lower OELV must not dominate the mixture.

Aluminium OEL: Why 'as Al' Is Missing

Thu, 16 Apr 2026 00:00:00 +0000

In 2010, the Dutch Health Council (Gezondheidsraad) established a health-based recommended occupational exposure limit of 0.05 mg/m³ (inhalable dust, 8-hour TWA) for aluminium chlorohydrate. A clear number — until you try to apply it to a different aluminium compound. The recommended value is expressed as mg compound/m³, not as mg Al/m³. That distinction is nowhere made explicit, and it has direct consequences for your risk assessment.

What the Health Council report says

In report GR2010/05OSH, the GBBS Committee proposes a health-based recommended OEL of 0.05 mg/m³ (inhalable dust, 8-hour TWA) for aluminium chlorohydrate (CAS 12042-91-0). The toxicological endpoint: chronic inflammation of lung tissue.

Recap: 34th NVvA Symposium 2026 — TrAHnsitie

Thu, 02 Apr 2026 00:00:00 +0000

On April 1-2, the 34th NVvA Symposium took place at the Woudschoten Conference Centre in Zeist, under the theme TrAHnsitie: The Occupational Hygienist as Strategic Partner in a Changing World. DOHSBase was present as a sponsor. In this article, we look back at the key sessions and developments.

AI in Occupational Hygiene: Opportunities and Challenges

One of the major themes of this year’s symposium was the role of artificial intelligence in occupational hygiene. Multiple speakers and initiatives were presented, including applications of AI in hazardous substance research and exposure modelling.

DOHSBase at the 34th NVvA Symposium 2026

Thu, 26 Mar 2026 00:00:00 +0000

DOHSBase is proud to participate as a sponsor at the 34th NVvA Symposium, taking place on April 1-2, 2026 at the Woudschoten Conference Centre in Zeist, the Netherlands.

TrAHnsitie: The Occupational Hygienist as Strategic Partner

This year’s theme — TrAHnsitie — focuses on the role of the occupational hygienist in a rapidly changing world. From the energy transition and digitalization to AI applications in occupational hygiene, the symposium covers the topics that will shape our sector in the years ahead.

ECHA Portal Links Restored in DOHSBase

Mon, 09 Feb 2026 00:00:00 +0000

The European Chemicals Agency (ECHA) recently migrated its online platform to a new infrastructure. As a result, over 500,000 deep links from DOHSBase to individual substance records on the ECHA portal stopped working. We have now resolved this issue, and all links are fully functional again.

What Is ECHA?

ECHA is the European Union agency responsible for the implementation of chemicals legislation. It manages one of the world’s largest databases of chemical substance information, including data on hazard classification, registration dossiers, and regulatory restrictions under REACH and CLP. For occupational hygienists, ECHA is a primary source of information on substance properties, harmonised classifications, and risk management measures.

Major Update to the Dutch Chemical Safety Dataset

Tue, 25 Nov 2025 00:00:00 +0000

We are pleased to announce a major update to the Dutch chemical safety dataset in DOHSBase Online. This release incorporates the latest regulatory information and occupational exposure limits for the Netherlands, and marks an important step forward in how we source and maintain this data.

What Has Changed

The November 2025 update includes the most recent Dutch regulatory data on chemical substances, including updated occupational exposure limits (grenswaarden), classification changes, and new substance entries. For occupational hygienists working in or with the Netherlands, this means that DOHSBase now reflects the current state of Dutch chemical safety regulation.

What's in a Name: Chromate

Thu, 25 Sep 2025 00:00:00 +0000

Following user feedback, the organic chromium compounds labelled “chromate” by ECHA have been removed from the CrVI category in DOHSBase. These compounds are trivalent (CrIII) and are not comparable to the much more dangerous hexavalent chromium (CrVI).

Context and scope

DOHSBase contains over 2,100 individual chromium compounds with valencies ranging from 1+ to 6+. Physical, chemical and toxicological properties differ markedly between and within the valency groups, and chemical stability varies greatly. With a single exception (butyl chromate), chromium compounds are solids that dissolve differently in water and other media.

Stoffenmanager Integration Restored

Fri, 29 Aug 2025 00:00:00 +0000

The data export from DOHSBase to Stoffenmanager is fully operational again. After a period of disruption, the integration has been restored, and users can once again export substance data directly from DOHSBase Online to their Stoffenmanager account.

Why This Integration Matters

Stoffenmanager is one of the most widely used tools in the Netherlands and across Europe for assessing exposure to hazardous substances. Many occupational hygienists use Stoffenmanager for their workplace risk assessments and rely on accurate substance data as input.

Webinar: Limit Values Hierarchy in DOHSBase

Thu, 23 Jan 2025 00:00:00 +0000

One of the key features of DOHSBase is the hierarchical presentation of occupational exposure limit values. In this webinar, we explain how the six hierarchy levels work and why the order of limit values matters.

The families of limit values

The DOHSBase hierarchy is built on the reliability of the underlying limit-value families. From the most reliable, unbiased health-based values at the top to modelling and expert judgment at the bottom — each tier plays its own role across compliance, safe work, and REACH product safety.

Webinar: SZW List 2026

Thu, 23 Jan 2025 00:00:00 +0000

The SZW List is updated annually with revised and new occupational exposure limits. In this webinar, we discuss the changes for 2026 and how they are processed in DOHSBase.

From “in any case” to a full overview

The SZW List is an “in any case” list: it names substances and groups that must be treated as CMR at minimum, but it does not cover every CMR substance. DOHSBase expands the list down to CAS level and supplements it with all other CMR classifications (CMR⁺) from ECHA CLH, the Dutch Health Council and other authoritative sources. The difference in counts is substantial:

Isocyanates: Exposure Limits Across Jurisdictions

Sat, 19 Oct 2024 00:00:00 +0000

Isocyanates are among the most important substance groups in occupational hygiene. They are potent sensitisers of the respiratory tract and a leading cause of occupational asthma worldwide. For occupational hygienists, navigating the various exposure limits for isocyanates across different jurisdictions is a recurring challenge. This article provides an overview of the current landscape.

Introduction: Why Isocyanates Demand Attention

Isocyanates are reactive chemicals widely used in the production of polyurethane foams, coatings, adhesives, and elastomers. The most common isocyanates encountered in occupational settings include toluene diisocyanate (TDI), methylene diphenyl diisocyanate (MDI), and hexamethylene diisocyanate (HDI).

IARC Cancer Evaluations in DOHSBase: Monographs 117-130 Added

Wed, 15 Mar 2023 00:00:00 +0000

Tracking which substances are classified as carcinogenic is one of the most important tasks in occupational hygiene. Multiple authoritative bodies publish cancer evaluations, and keeping up with all of them is a challenge. DOHSBase brings these sources together in one place, and the latest update adds IARC monographs volumes 117 through 130 as linked PDF references.

Why Carcinogen Tracking Matters

Under EU and national regulations, employers have specific obligations when workers are exposed to carcinogenic substances. These obligations include substitution requirements, exposure minimisation, registration and health surveillance. Identifying whether a substance is classified as carcinogenic — and by which authority — is therefore the starting point for any exposure assessment involving potential carcinogens.

New Dutch Legal Limit Values: What Changed in December 2022

Fri, 27 Jan 2023 00:00:00 +0000

On 12 December 2022, new Dutch legal occupational exposure limits were published in Staatscourant nr 32933. These changes have been integrated into DOHSBase and contain several noteworthy updates that affect day-to-day exposure assessment.

1. Gas and Vapour Substances Now Have ppm Values

Previously, Dutch legal limit values for gases and vapours were expressed only in mg/m3. The updated regulation now also provides values in ppm (parts per million) for applicable substances. This is a practical improvement: ppm values are temperature- and pressure-independent, making them easier to work with in field measurements and when comparing values across jurisdictions.

CGC Meeting: Group Approach to Substance Assessment

Wed, 06 Apr 2022 00:00:00 +0000

In March 2022, DOHSBase participated in the Contact Group Health and Chemistry (CGC) meeting, where the topic was the “Group approach to substances for hazard and risk assessment in the workplace.” This is a subject at the core of what DOHSBase does.

Why a Group Approach Matters

Many workplace substances do not have individual occupational exposure limits. However, they often belong to a well-defined chemical group where the hazard profile is driven by a common structural element or functional group. Applying group limit values, group classifications and group assessment methods allows occupational hygienists to evaluate these substances even when substance-specific data is lacking.

DOHSBase Update August 2021: SZW List, Isocyanates and More

Wed, 01 Sep 2021 00:00:00 +0000

The August 2021 DOHSBase update brings several important changes across multiple data sources. Here is an overview of what has been added and improved.

SZW List July 2021

The latest SZW list (July 2021) has been fully integrated into DOHSBase. This list, published by the Dutch Ministry of Social Affairs and Employment, contains legally binding occupational exposure limits and classifications for carcinogenic, mutagenic and reprotoxic substances. All limit values and CMR classifications from this edition are now reflected in DOHSBase.

The Science Behind Kick-Off Values: Our 2016 Peer-Reviewed Research on Hazard Banding

Thu, 01 Dec 2016 00:00:00 +0000

In 2016, DOHSBase’s Theo Scheffers and five co-authors published a peer-reviewed study in Annals of Occupational Hygiene that examined a fundamental question in occupational hygiene: how reliable is hazard banding as a method for estimating safe exposure levels?

The paper — “On the Strength and Validity of Hazard Banding” — provides the scientific validation behind the approach that powers DOHSBase’s kick-off values: grouping substances by their GHS/CLP hazard classification and deriving exposure benchmarks from the statistical distribution of known occupational exposure limits within each group.

From 1,000 to 325,000 Substances: The 1994 Article That Introduced DOHS-Base

Tue, 01 Mar 1994 00:00:00 +0000

In 1994, a two-page article appeared in Arbeidsomstandigheden — the leading Dutch journal for occupational health and safety at the time. Written by Leendert Meijers of TNO and Theo Scheffers, it announced the release of DOHS-Base 2.0: a database of chemical substance information for occupational hygienists, now extended with company-specific limit values (bedrijfsgrenswaarden).

The article, titled “DOHS-Base 2.0 opengesteld voor bedrijfsgrenswaarden”, was published in volume 70, number 3 (pages 149-150). We recently rediscovered this publication on the TNO publications archive, and it provides a fascinating window into the origins of what is now DOHSBase Online.