The file D9_England_Wales.csv contains the contaminant concentrations in shellfish from the waters around England and Wales used in 'Contaminants in Seafood', a Descriptor 9 Indicator in the UK's 2025 Marine Strategy Assessment. The data were reported by the Food Standards Agency and downloaded from Chemical contaminant results for England and Wales.

The file is UTF-8-BOM encoded so can be read directly into Excel, or into R using the function read.csv with the argument fileEncoding = “UTF-8-BOM”.

The variables in the file are:

MSFD_subregion
Description: Marine Strategy Framework Directive subregion
Unit:
Type: categorical
Levels: Greater North Sea, Celtic Seas
Note: in the map of biogeographic regions the Greater North Sea comprises the Northern North Sea, Southern North Sea, and Eastern Channel, whilst the Celtic Seas comprises the Western Channel and Celtic Sea, Irish Sea, Minches and Western Scotland, Scottish Continental Shelf, and Atlantic North-West Approaches.

biogeographic_region
Description: biogeographic region
Unit:
Type: categorical
Levels: Southern North Sea, Eastern Channel, Western Channel and Celtic Sea, Irish Sea
Note: there are 8 biogeographic regions but only 4 with data

production_area
Description: shellfish production area
Unit:
Type: categorical
Levels: 14
Note:

site_name
Description: name of sampling station
Unit:
Type: categorical
Levels: 14
Note:

sample_date
Description: sampling date
Unit: YYYY-MM-DD
Type: discrete
Range: 2016-11-16, 2020-03-10
Note:

sample_latitude
Description: sampling latitude
Unit: decimal degrees
Type: continuous
Range: 49.90, 53.73
Note:

sample_longitude
Description: sampling longitude
Unit: decimal degrees
Type: continuous
Range: -5.67, 0.68
Note:

benz[a]anthracene_mg_per_kg
Description: concentration of benz[a]anthracene in shellfish soft-body tissue
Unit: mg/kg wet (fresh) weight
Type: continous, but stored as a character vector to accommodate censored (less-than) measurements
Range: <0.5, 3.98
Note:

chrysene_mg_per_kg
Description: concentration of chrysene in shellfish soft-body tissue
Unit: mg/kg wet (fresh) weight
Type: continuous
Range: 0.37, 4.04
Note:

benzo[b]fluoranthene_mg_per_kg
Description: concentration of benzo[b]fluoranthene in shellfish soft-body tissue
Unit: mg/kg wet (fresh) weight
Type: continuous
Range: 0.26, 8.04
Note:

benzo[a]pyrene_mg_per_kg
Description: concentration of benzo[a]pyrene in shellfish soft-body tissue
Unit: mg/kg wet (fresh) weight
Type: continous, but stored as a character vector to accommodate censored (less-than) measurements
Range: <0.5, 3.44
Note:

sum_PAH_4_lower_mg_per_kg
Description: summed concentration of benz[a]anthracene, benzo[a]pyrene, benzo[b]fluoranthene and chrysene in shellfish soft-body tissue
Unit: mg/kg wet (fresh) weight
Type: continuous
Range: 1.26, 19.5
Note: 'lower' in the variable name indicates an adjustment in the summation to accommodate censored (less-than) measurements

cadmium_mg_per_kg
Description: concentration of cadmium in shellfish soft-body tissue
Unit: mg/kg wet (fresh) weight
Type: continuous
Range: 0.023, 0.22
Note:

mercury_mg_per_kg
Description: concentration of mercury in shellfish soft-body tissue
Unit: mg/kg wet (fresh) weight
Type: continuous
Range: 0.007, 0.024
Note:

lead_mg_per_kg
Description: concentration of lead in shellfish soft-body tissue
Unit: mg/kg wet (fresh) weight
Type: continuous
Range: 0.034, 0.41
Note:

sum_dioxins_ng_per_kg
Description: summed (toxic equivalent) concentration of dioxins and furans in shellfish soft-body tissue
Unit: ng/kg wet (fresh) weight
Type: continuous
Range: 0.5, 0.5
Note: uses the 2005 World Health Organisation compounds and toxic equivalency factors

sum_dioxins_and_dioxin_like_PCBs_ng_per_kg
Description: summed (toxic equivalent) concentration of dioxins, furans and dioxin-like (planar) polychlorinated biphenyls in shellfish soft-body tissue
Unit: ng/kg wet (fresh) weight
Type: continuous
Range: 0.81, 0.81
Note: uses the 2005 World Health Organisation compounds and toxic equivalency factors

sum_ICES_6_PCBs_ug_per_kg
Description: summed concentration of the ICES 6 (non-planar) polychlorinated biphenyls
Unit: ug/kg wet (fresh) weight
Type: continuous
Range: 3.64, 3.64
Note: the ICES 6 (non-planar) polychlorinated biphenyls are CB28, CB52, CB101, CB138, CB153 and CB180

comments
Description: summary of results
Unit:
Type: categorical
Levels: All results below maximum permitted levels
Note: