The following Pesticide Hazard Tricolour (PHT) alerts are based on the data in the tables below. An absence of an alert does not imply the substance has no implications for human health, biodiversity or the environment but just that we do not have the data to form a judgement. The alerts for Highly Hazardous Pesticides (HHPs) are based on applying the FAO/WHO (Type 1) and the PAN (Type II) criteria to PPDB data. Further details on the HHP indicators are given in the tables below. Neither the PHT nor the HHP hazard alerts take account of usage patterns or exposure, thus they do not represent risk.
PHT: Environmental fate
PHT: Ecotoxicity
PHT: Human health
Highly Hazardous Pesticide
Environmental fate High alert: GUS: High leachability; Drainflow: Very mobile
Detected in US drinking waters. Specific quality standards in EU/GB not set.
Forever chemical
-
Highly Hazardous Pesticide (HHP)
Type I
Yes [
C4 Criterion 4: Pesticide active ingredients that meet the criteria of reproductive toxicity Categories 1A and 1B of the Globally Harmonized System on Classification and Labelling of Chemicals (GHS) (those with a CLP classification of H360)
]
Type II
Yes [
R04 Rule 4: Pesticide active ingredients that meet the criteria of reproductive toxicity Categories 1A and 1B of the Globally Harmonized System on Classification and Labelling of Chemicals (GHS) (those with a CLP classification of H360)
]
Other status information
PAN Bad Actor Chemical; This substance is a restricted co‑formulant in EU under Regulation (EC) No 1107/2009; REACH registered.
Herbicide Resistance Class (HRAC MoA class)
Not applicable
Herbicide Resistance Class (WSSA MoA class)
Not applicable
Insecticide Resistance Class (IRAC MoA class)
Not applicable
Fungicide Resistance Class (FRAC MOA class)
Not applicable
Examples of recorded resistance
-
Physical state
Clear, colourless oily liquid with a fishy odour when pure. Yellow when impure.
Commercial production of N methyl 2 pyrrolidone (NMP) is based on the amine catalysed conversion of γ butyrolactone (GBL) with methylamine in a continuous high temperature process. Industrial plants feed GBL and anhydrous methylamine into a fixed bed or liquid phase reactor operated at very high temperatures and elevated pressure to drive ring opening and subsequent N methylation, forming NMP with high selectivity. The crude reaction mixture is then purified through fractional distillation, removing unreacted amines, water, and GBL, yielding NMP at grades depending on the degree of downstream refining.
Impact on climate of production and use
The climate change impact of N methyl 2 pyrrolidone (NMP) arises almost entirely from its fossil based production chain, not from the chemical itself. Industrial NMP synthesis uses feedstocks derived from petrochemical routes, processes that consume significant energy and generate CO₂ emissions. Ethoxylation type steps are absent, but the high temperature, high pressure lactam formation still carries a measurable embedded carbon footprint. Downstream, NMP is stable and non volatile, so it does not act as a greenhouse gas; its contribution to climate change is therefore indirect, driven by upstream industrial energy use and the broader emissions associated with sectors that rely on NMP. A recent report gave a cradle to gate carbon footprint of approximately 6.3 kg CO₂-e per kg NMP produced.
ENVIRONMENTAL FATE
Property
Value
Source; quality score; and other information
Interpretation
Solubility - In water at 20 °C at pH 7 (mg l⁻¹)
1000000
V3 V = ChemID Online Databases; Chemspider; PubChem. (ChemID ) 3 = Unverified data of known source
High
Solubility - In organic solvents at 20 °C (mg l⁻¹)
Miscible
V3 V = ChemID Online Databases; Chemspider; PubChem. (ChemID ) 3 = Unverified data of known source
Acetone
-
Miscible
V3 V = ChemID Online Databases; Chemspider; PubChem. (ChemID ) 3 = Unverified data of known source
Ethyl acetate
-
Miscible
V3 V = ChemID Online Databases; Chemspider; PubChem. (ChemID ) 3 = Unverified data of known source
Ethanol
-
Miscible
V3 V = ChemID Online Databases; Chemspider; PubChem. (ChemID ) 3 = Unverified data of known source
Benzene
-
Melting point (°C)
-24.4
E3 E = Manufacturers safety data sheets 3 = Unverified data of known source
-
Boiling point (°C)
203
E3 E = Manufacturers safety data sheets 3 = Unverified data of known source
-
Degradation point (°C)
-
-
-
Flashpoint (°C)
95
E3 E = Manufacturers safety data sheets 3 = Unverified data of known source
-
Octanol-water partition coefficient at pH 7, 20 °C
P
4.17 X 10-01
Calculated
-
Log P
-0.38
F3 F = U.S. EPA ECOTOX database / U.S. EPA pesticide fate database / Miscellaneous WHO documents / FAO data, IPCS INCHEM data (US EPA Databases Related to Pesticide Risk Assessment ) 3 = Unverified data of known source
Low
Fat solubility of residues
Solubility
Insoluble
R3 R = Peer reviewed scientific publications 3 = Unverified data of known source
-
Data type
Research study
R3 R = Peer reviewed scientific publications 3 = Unverified data of known source
-
Density (g ml⁻¹)
1.028
E3 E = Manufacturers safety data sheets 3 = Unverified data of known source
-
Dissociation constant pKa) at 25 °C
-
-
-
-
Vapour pressure at 20 °C (mPa)
3.9 X 1004
F3 F = U.S. EPA ECOTOX database / U.S. EPA pesticide fate database / Miscellaneous WHO documents / FAO data, IPCS INCHEM data (US EPA Databases Related to Pesticide Risk Assessment ) 3 = Unverified data of known source
Highly volatile. If applied directly to plants or soil, drift is a concern & mitigation is advisable
Henry's law constant at 25 °C (Pa m³ mol⁻¹)
-
-
-
Volatilisation as max % of applied dose lost
From plant surface
-
-
-
From soil surface
-
-
-
Maximum UV-vis absorption L mol⁻¹ cm⁻¹
205nm = Log E 3.46
V3 V = ChemID Online Databases; Chemspider; PubChem. (ChemID ) 3 = Unverified data of known source
-
Surface tension (mN m⁻¹)
40.7
F3 F = U.S. EPA ECOTOX database / U.S. EPA pesticide fate database / Miscellaneous WHO documents / FAO data, IPCS INCHEM data (US EPA Databases Related to Pesticide Risk Assessment ) 3 = Unverified data of known source
-
Degradation
Property
Value
Source; quality score; and other information
Interpretation
General biodegradability
Readily biodegrdable. Approx. 97% degradation in 7 days.
Soil degradation (days) (Aerobic conditions)
DT₅₀ (typical)
8.0
R3 R = Peer reviewed scientific publications 3 = Unverified data of known source
Non-persistent
DT₅₀ (lab at 20 °C)
8.0
R3 R = Peer reviewed scientific publications 3 = Unverified data of known source
Non-persistent
DT₅₀ (field)
-
-
-
DT₉₀ (lab at 20 °C)
-
-
-
DT₉₀ (field)
-
-
-
DT₅₀ modelling endpoint
-
-
-
Note
General literature: DT₅₀ 4.0 days (clay), 8.7 days (loam), and 11.5 days (sand)
Soil mineralisation
Aerobic (at 20 °C)
-
-
-
Anaerobic (at 20 °C)
-
-
Dissipation rate RL₅₀ (days) on plant matrix
Value
-
-
-
Note
-
Dissipation rate RL₅₀ (days) on and in plant matrix
Value
-
-
-
Note
-
Aqueous photolysis DT₅₀ (days) at pH 7
Value
-
-
-
Note
-
Aqueous hydrolysis DT₅₀ (days) at 20 °C and pH 7
Value
-
-
-
Note
-
Water-sediment DT₅₀ (days)
-
-
-
Water phase only DT₅₀ (days)
-
-
-
Sediment phase only DT₅₀ (days)
-
-
-
Air degradation
As this parameter is not normally measured directly, a surrogate measure is used: ‘Photochemical oxidative DT₅₀’. Where data is available, this can be found in the Fate Indices section below.
Decay in stored produce DT₅₀
-
Soil adsorption and mobility
Property
Value
Source; quality score; and other information
Interpretation
Linear
Kd (mL g⁻¹)
-
Q3 Q = Miscellaneous data from online sources 3 = Unverified data of known source
Very mobile
Koc (mL g⁻¹)
5
Notes and range
Estimated
Freundlich
Kf (mL g⁻¹)
-
-
-
Kfoc (mL g⁻¹)
-
1/n
-
Notes and range
-
pH sensitivity
-
Fate indices
Property
Value
Source; quality score; and other information
Interpretation
GUS leaching potential index
2.98
Calculated
High leachability
SCI-GROW groundwater index (μg l⁻¹) for a 1 kg ha⁻¹ or 1 l ha⁻¹ application rate
Value
3.82 X 10-02
Calculated
-
Note
-
Potential for particle bound transport index
Low
Calculated
-
Potential for loss via drain flow
Very mobile
Calculated
-
Photochemical oxidative DT₅₀ (hrs) as indicator of long-range air transport risk
5.2
F3 F = U.S. EPA ECOTOX database / U.S. EPA pesticide fate database / Miscellaneous WHO documents / FAO data, IPCS INCHEM data (US EPA Databases Related to Pesticide Risk Assessment ) 3 = Unverified data of known source
Calculated using the Atkinson method. Assumed 1.5E+06 OH/cm³, 12 hr. EU trigger for long-range transport is DT₅₀ in air <2 days.
Below the level of concern for long-range air transport
Bio-concentration factor
BCF (l kg⁻¹)
3.0
F3 F = U.S. EPA ECOTOX database / U.S. EPA pesticide fate database / Miscellaneous WHO documents / FAO data, IPCS INCHEM data (US EPA Databases Related to Pesticide Risk Assessment ) 3 = Unverified data of known source
Estimated
Low potential
CT₅₀ (days)
ND
-
Known metabolites
None
ECOTOXICOLOGY
Terrestrial ecotoxicology
Property
Value
Source; quality score; and other information
Interpretation
Mammals - Acute oral LD₅₀ (mg kg⁻¹)
3914
E3 E = Manufacturers safety data sheets 3 = Unverified data of known source
Rat
Low
Mammals - Short Term Oral NOAEL (mg kg⁻¹ bw d⁻¹)
-
-
-
Mammals - Long Term (Chronic) Oral NOAEL (mg kg⁻¹ bw d⁻¹)
Contact acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg bee⁻¹)
> 200
F3 F = U.S. EPA ECOTOX database / U.S. EPA pesticide fate database / Miscellaneous WHO documents / FAO data, IPCS INCHEM data (US EPA Databases Related to Pesticide Risk Assessment ) 3 = Unverified data of known source
Apis mellifera adults
Low
Oral acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg bee⁻¹)
5.0
R3 R = Peer reviewed scientific publications 3 = Unverified data of known source
Apis mellifera sublethal EC₅₀
Moderate
Unknown mode acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg bee⁻¹)
-
-
-
Chronic LOEC, Oral
16.0
R3 R = Peer reviewed scientific publications 3 = Unverified data of known source
Apis mellifera Larvae
-
Notes
-
Bumblebees (Bombus spp.)
Contact acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg bee⁻¹)
-
-
-
-
Oral acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg bee⁻¹)
-
-
-
-
Mason bees (Osmia spp.)
Contact acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg bee⁻¹)
-
-
-
Oral acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg bee⁻¹)
-
-
-
Other bee species (1)
Acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg insect⁻¹)
-
-
-
Mode of exposure
-
Other bee species (2)
Acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg insect⁻¹)
-
-
-
Mode of exposure
-
Beneficial insects (Ladybirds)
-
-
-
Beneficial insects (Lacewings)
-
-
-
Beneficial insects (Parasitic wasps)
-
-
-
Beneficial insects (Predatory mites)
-
-
-
Beneficial insects (Ground beetles)
-
-
-
Beneficial insects (Butterflies)
Contact
-
-
-
Notes
-
Oral
-
-
-
Notes
-
Aquatic ecotoxicology
Property
Value
Source; quality score; and other information
Interpretation
Temperate Freshwater Fish - Acute 96 hour LC₅₀ (mg l⁻¹)
F3 F = U.S. EPA ECOTOX database / U.S. EPA pesticide fate database / Miscellaneous WHO documents / FAO data, IPCS INCHEM data (US EPA Databases Related to Pesticide Risk Assessment ) 3 = Unverified data of known source
A0 A = Chromosome aberration (EFSA database) 0 = No data
;
B0 B = DNA damage/repair (EFSA database) 0 = No data
;
C0 C = Gene mutation (EFSA database) 0 = No data
;
D0 D = Genome mutation (EFSA database) 0 = No data
;
E3 E = Unspecified genotoxicity type (miscellaneous data source) 3 = Negative
?Possibly, status not identified
Reproduction / development effects
Acetyl cholinesterase inhibitor
Neurotoxicant
✓Yes, known to cause a problem
XNo, known not to cause a problem
?Possibly, status not identified
Respiratory tract irritant
Skin irritant
Skin sensitiser
✓Yes, known to cause a problem
✓Yes, known to cause a problem
No data found
Eye irritant
Phototoxicant
✓Yes, known to cause a problem
No data found
General human health issues
Causes irritation to the gastrointestinal tract May cause corneal clouding Possible kidney toxicant May cause dermatitis
Handling issues
Property
Value and interpretation
General
Flammable Explosive air-vapour mixes may form above 96 DegC Incompatible with strong oxidants, acids & bases Hygroscopic Will release toxic funes when heated
Tzilivakis, J., Lewis, K.A., Green, A. and Warner, D.J. (2026) A decade of growth and impact of the Pesticide Properties Database (PPDB). Human and Ecological Risk Assessment: An International Journal, 32(6), 1104-1129. DOI: 10.1080/10807039.2026.2702066
Lewis, K.A., Tzilivakis, J., Warner, D. and Green, A. (2016) An international database for pesticide risk assessments and management. Human and Ecological Risk Assessment: An International Journal, 22(4), 1050-1064. DOI: 10.1080/10807039.2015.1133242
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Environmental fate
Ecotoxicity
Highly Hazardous Pesticide (HHP)
