ON CTIVES A - Marine Science
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Andrés Molina Grupo de Investigación en Ecología y Contaminación Acuática. Instituto de Estudios en Ciencias del Mar (CECIMAR), Universidad Nacional de Colombia, Sede Caribe aemolinas@unal .edu.co Guillermo Duque Universidad Nacional de Colombia, Sede Palmira. Facultad de Ingeniería y Administración. gduquen@unal .edu.co Pilar Cogua Universidad Santiago de Cali. Facultad de Ciencias Básicas. rosa [email protected] INTRODUCTION OBJECTIVES STUDY AREA METHODOLOGY RESULTS AND DISCUSSION CONCLUSIONS REFERENCES The population of Buenaventura Bay rely on artisanal fisheries for their survival, where the catfish Cathorops multiradiatus is highly consumed and represent a species of cultural significance. This estuary is highly exposed to different pollutants, such as mercury among many others, and active mercury bioaccumulation processes have been reported in this estuary (Duque and Cogua P. 2016; Gamboa-García et al., 2020). To determine the dynamics of mercury accumulation and the consumption risk of C. multiradiatus in Buenaventura Bay The Buenaventura Bay estuary is located in the Colombian Pacific (Tropical Eastern Pacific). From January to June, the average monthly precipitation is 200 to 500 mm, dry season, and from July to December, 500 to ˃700 mm, rainy season (IDEAM). It has two main tributary rivers, Anchicayá and Dagua (427 m3 s-1), which are affected by illegal gold mining. This ecosystem is highly intervened, with approximately 300,000 inhabitants and the most important port in Colombia. - Day JW, Crump BC, Michael, Kemp W, Yáñez-Arancibia A (2012) Estuarine Ecology. John Wiley & Sons, Inc., Hoboken, NJ, USA - Duque G. and Cogua P. 2016. Mercurio en peces de la bahía de Buenaventura. Ingenium 10: 11–17. - EPA. 1989. Risk Assessment Guidance for Superfund (Volume I) Human Health Evaluation Manual. U.S. Environmental Protection Agency. Washington D.C. - EPA. 2000. Guidance for Assessing Chemical Contaminant Data for Use in Fish Advisories (Volume 2) Risk Assessment and Fish Consumption Limits, Third Edition. U.S. Environmental Protection Agency. Washington D.C. - Gamboa-García DE, Duque G, Cogua P, Marrugo-Negrete JL (2020) Mercury dynamics in macroinvertebrates in relation to environmental factors in a highly impacted tropical estuary: Buenaventura Bay, Colombian Pacific. Environ Sci Pollut Res 27:4044–4057. doi: 10.1007/s11356-019-06970-6 - He M, Tian L, Braaten HFV, et al (2019) Mercury–Organic Matter Interactions in Soils and Sediments: Angel or Devil? Bull Environ Contam Toxicol 102:621–627. doi: 10.1007/s00128-018-2523-1 For this research, the estuary was divided into four areas according to salinity gradient, geomorphology and environmental characteristics, two in the inner part and two in the outer part of the bay (Figure 1). Fish samples were collected using an artisanal trawl between april and september of 2015. Before each trawling, the environmental variables were measured in the water column, and sediment samples were taken to determine the content of Organic Matter (OM; %) and total mercury. The risk assessment was calculated based on the hazard index proposed by EPA (1989) and EPA (2000). The calculations were made for a person weighing 70 kg and assuming a reference dose proposed by the EPA (0,1 μg/kg/day) and using Methil- mercury (MeHg) concentrations. HI: HazardIndex E: Exposure Level RfD: Reference Dose = = ∗ C: Average concentration of MeHg I: Daily fish intake W: Average weight of a person The dynamics of the environmental variables (salinity, temperature, dissolved oxygen and pH) suggested that Buenaventura bay is a positive estuary. Temporally, the highest values in all variables occurred in the dry season and spatially in the external part of the estuary (Table 1), probably associated with hydroclimatic variations and estuary ecoclines (Day et al., 2012). Table 1. Environmental variables. Significant differences are represented by lowercase letters, post hoc tests Permanova pair test (p (PERM) <0.05). In this study 103 individuals were caught, presenting an average weight of 53.24 ± 5.25 g and an average total length of 18.08 ± 1.78 cm. The average of THg content in C. multiradiatus was 0.312±0.149 μg g -1 . The highest THg content in this species was recorded in the rainy season and in the external zone of the estuary (Figure 2). Figure 2. THg concentration in muscle of C. multiradiatus standardized by size, in function of the seasons and sampling areas. Significant differences are represented by lowercase letters, Permanova pair-wise test (p (PERM) <0.05). Regarding the interaction of different environmental variables on the THg concentrations in muscle of C. multiradiatus (multivariate GAM), the model includes the variables temperature (non-linear) and dissolved oxygen (linear), in a non- significant way and salinity and THg in sediments with a non-linear and significant fit, with an explained deviation of 44.1%. The higher concentrations of THg in muscle were associated with salinities between 22 and 27 PSU and THg in sediments less than 0.06 μg g -1 (Figure 3). The greater accumulation of HgT in C. multiradiatus in the external estuary, an area with the lowest concentration of HgT in sediments, may be mediated by variations in the bioavailability of mercury related to physicochemical changes, represented by variations in salinity (He et al., 2019). Figure 3. Environmental variables with significant non- linear correlation on THg in muscle of C. multiradiatus (multivariate GAM). The y-axis represents the HgT in fish under a smoothed function of the environmental variables a) salinity (Salt) and b) THg in sediments (THg Sed). Furthermore, 75% of the fishes captured had mercury contents greater than 0.2 μg g-1, representing a risk of consumption for the vulnerable population. In other words, it only takes a daily consumption above 25 g of C. multiradiatus, to represent a risk to human health over time. Figure 4. Amount of C. multiradiatus that can be eaten daily without risk. o The average of THg content in C. multiradiatus was 0.312±0.149 μg g-1, and 75% of the fishes captured had mercury contents greater than 0.2 μg g-1, representing a risk of consumption for the vulnerable population. o The higher concentrations of THg in C. multiradiatus were associated with salinities between 22 and 27 PSU and THg in sediments less than 0.06 μg g-1. o Bioavailability of HgT in biotic and abiotic compartments was influential in the accumulation of this heavy metal in the box sea catfish, C. multiradiatus. o A daily consumption of C. multiradiatus, a species of cultural significance, greater than 25 g, may represent a risk to human health,. Figure 1. Buenaventura Bay: study areas and sampling stations a a ab b Dry Rainy
Transcript of ON CTIVES A - Marine Science
Andrés Molina Grupo de Investigación en Ecología y Contaminación Acuática. Instituto de Estudios en Ciencias del Mar (CECIMAR),
Universidad Nacional de Colombia, Sede Caribe [email protected]
Guillermo Duque Universidad Nacional de Colombia, Sede Palmira. Facultad de Ingeniería y Administración. [email protected]
Pilar Cogua Universidad Santiago de Cali. Facultad de Ciencias Básicas. [email protected]
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The population of Buenaventura Bay rely on artisanal
fisheries for their survival, where the catfish Cathorops
multiradiatus is highly consumed and represent a
species of cultural significance. This estuary is highly
exposed to different pollutants, such as mercury among
many others, and active mercury bioaccumulation
processes have been reported in this estuary (Duque
and Cogua P. 2016; Gamboa-García et al., 2020).
To determine the
dynamics of mercury
accumulation and the
consumption risk of C.
multiradiatus in
Buenaventura Bay
The Buenaventura Bay estuary is located in the Colombian
Pacific (Tropical Eastern Pacific). From January to June, the
average monthly precipitation is 200 to 500 mm, dry season,
and from July to December, 500 to ˃700 mm, rainy season
(IDEAM). It has two main tributary rivers, Anchicayá and Dagua
(427 m3 s-1), which are affected by illegal gold mining. This
ecosystem is highly intervened, with approximately 300,000
inhabitants and the most important port in Colombia.
- Day JW, Crump BC, Michael, Kemp W, Yáñez-Arancibia A (2012) Estuarine Ecology. John Wiley & Sons,
Inc., Hoboken, NJ, USA
- Duque G. and Cogua P. 2016. Mercurio en peces de la bahía de Buenaventura. Ingenium 10: 11–17.
- EPA. 1989. Risk Assessment Guidance for Superfund (Volume I) Human Health Evaluation Manual. U.S.
Environmental Protection Agency. Washington D.C.
- EPA. 2000. Guidance for Assessing Chemical Contaminant Data for Use in Fish Advisories (Volume 2)
Risk Assessment and Fish Consumption Limits, Third Edition. U.S. Environmental Protection Agency.
Washington D.C.
- Gamboa-García DE, Duque G, Cogua P, Marrugo-Negrete JL (2020) Mercury dynamics in
macroinvertebrates in relation to environmental factors in a highly impacted tropical estuary: Buenaventura
Bay, Colombian Pacific. Environ Sci Pollut Res 27:4044–4057. doi: 10.1007/s11356-019-06970-6
- He M, Tian L, Braaten HFV, et al (2019) Mercury–Organic Matter Interactions in Soils and Sediments:
Angel or Devil? Bull Environ Contam Toxicol 102:621–627. doi: 10.1007/s00128-018-2523-1
For this research, the estuary was divided into four areas
according to salinity gradient, geomorphology and environmental
characteristics, two in the inner part and two in the outer part of
the bay (Figure 1). Fish samples were collected using an
artisanal trawl between april and september of 2015. Before
each trawling, the environmental variables were measured in the
water column, and sediment samples were taken to determine
the content of Organic Matter (OM; %) and total mercury.
The risk assessment was calculated
based on the hazard index proposed
by EPA (1989) and EPA (2000). The
calculations were made for a person
weighing 70 kg and assuming a
reference dose proposed by the EPA
(0,1 µg/kg/day) and using Methil-
mercury (MeHg) concentrations.
HI: HazardIndex
E: Exposure Level
RfD: Reference Dose𝐻𝐼 =
𝐸
𝑅𝑓𝐷
𝐸 =𝐶 ∗ 𝐼
𝑊
C: Average
concentration of MeHg
I: Daily fish intake
W: Average weight of a
person
The dynamics of the environmental variables (salinity, temperature,
dissolved oxygen and pH) suggested that Buenaventura bay is a positive
estuary. Temporally, the highest values in all variables occurred in the dry
season and spatially in the external part of the estuary (Table 1), probably
associated with hydroclimatic variations and estuary ecoclines (Day et al.,
2012).
Table 1. Environmental variables. Significant differences are represented by lowercase letters, post
hoc tests Permanova pair test (p (PERM) <0.05).
In this study 103 individuals were caught, presenting an average weight of
53.24 ± 5.25 g and an average total length of 18.08 ± 1.78 cm. The average
of THg content in C. multiradiatus was 0.312±0.149 µg g-1. The highest THg
content in this species was recorded in the rainy season and in the external
zone of the estuary (Figure 2).
Figure 2. THg concentration
in muscle of C. multiradiatus
standardized by size, in
function of the seasons and
sampling areas. Significant
differences are represented
by lowercase letters,
Permanova pair-wise test (p
(PERM) <0.05).
Regarding the interaction of different environmental variables on the THg
concentrations in muscle of C. multiradiatus (multivariate GAM), the model includes
the variables temperature (non-linear) and dissolved oxygen (linear), in a non-
significant way and salinity and THg in sediments with a non-linear and significant
fit, with an explained deviation of 44.1%. The higher concentrations of THg in
muscle were associated with salinities between 22 and 27 PSU and THg in
sediments less than 0.06 µg g-1 (Figure 3). The greater accumulation of HgT in C.
multiradiatus in the external estuary, an area with the lowest concentration of HgT
in sediments, may be mediated by variations in the bioavailability of mercury related
to physicochemical changes, represented by variations in salinity (He et al., 2019).
Figure 3. Environmental
variables with significant non-
linear correlation on THg in
muscle of C. multiradiatus
(multivariate GAM). The y-axis
represents the HgT in fish
under a smoothed function of
the environmental variables
a) salinity (Salt) and b) THg in
sediments (THg Sed).
Furthermore, 75% of the fishes
captured had mercury contents
greater than 0.2 µg g-1,
representing a risk of
consumption for the vulnerable
population. In other words, it
only takes a daily consumption
above 25 g of C. multiradiatus,
to represent a risk to human
health over time.Figure 4. Amount of C. multiradiatus that can be eaten
daily without risk.
o The average of THg content in C. multiradiatus was 0.312±0.149 µg g-1, and
75% of the fishes captured had mercury contents greater than 0.2 µg g-1,
representing a risk of consumption for the vulnerable population.
o The higher concentrations of THg in C. multiradiatus were associated with
salinities between 22 and 27 PSU and THg in sediments less than 0.06 µg g-1.
o Bioavailability of HgT in biotic and abiotic compartments was influential in the
accumulation of this heavy metal in the box sea catfish, C. multiradiatus.
o A daily consumption of C. multiradiatus, a species of cultural significance,
greater than 25 g, may represent a risk to human health,.
Figure 1. Buenaventura Bay: study
areas and sampling stations
a
a
ab
b
Dry Rainy
Salinity
(PSU)
Temperature
(°C)
DO
(mg l-1)pH OM%
THg in
sediments (µg/g)
SeasonsDry 25.9±2.9 a 29.6±1.1 a 6.0±0.6 7.9±0.3 a 5.3±2.9 b 0.051±0.033 b
Rainy 19.1±3.9 b 28.7±0.6 b 5.9±1.0 7.8±0.2 b 7.2±3.5 a 0.089±0.041 a
Area
A1 20.7±5.8 b 28.9±0.7 5.5±0.7 bc 7.7±0.1 c 7.0±3.1 a 0.079±0.035 a
A2 22.2±3.8 ab 29.1±0.5 5.4±0.4 c 7.8±0.1 bc 7.7±2.6 a 0.096±0.038 a
A3 23.6±4.8 a 29.0±1.3 6.1±0.6 ab 7.9±0.4 ab 3.1±1.7 b 0.032±0.027 b
A4 23.6±4.7 a 29.5±1.0 6.6±0.9 a 8.0±0.1 a 7.3±3.5 a 0.073±0.041 a
