*4.2.1 Petroleum (PAHs)*

The results on PAHs indicate that these compounds are widely distributed in coastal areas and are stored in lagoons, estuaries, and wetlands. There is abundant

**15**

*Pollution Issues in Coastal Lagoons in the Gulf of Mexico DOI: http://dx.doi.org/10.5772/intechopen.86537*

adverse biological effects [46].

in the Mecoacan lagoon with 18.78 μg g<sup>−</sup><sup>1</sup>

**Cd (μg g<sup>−</sup><sup>1</sup> )**

*Average levels of pollutants in sediments of the four lagoons analyzed.*

**Cr (μg g<sup>−</sup><sup>1</sup> )**

*4.2.2 Metals*

48.30 μg g<sup>−</sup><sup>1</sup>

**Area PAHs** 

Tampamachoco lagoon system (TLS)

Mandinga lagoon system (TLS)

Alvarado lagoon system

Terminos lagoon system (TELS)

Yucateco lagoon, Tabasco state

Mecoacan, Tabasco state

**Table 2.**

**(μg g<sup>−</sup><sup>1</sup> )**

(1.84 and 1.46 μg g<sup>−</sup><sup>1</sup>

literature on this [49] and thanks to the use of sedimentary cores we know that these pollutants have been introduced to the lagoons more than 50 years ago and that their presence can originate as waste from oil activities or by the pyrolysis such as volcanism, burning of coal, burning of pastures and forest fires. Regarding its presence, the dominant PAHs are formed by four rings (pyrolytic) such as chrysene, benzo[a]anthracene, benzo[k]fluoranthene and benzo[b]fluoranthene. In general, their concentrations do not exceed the criterion of maximum concentration to cause

Comparing the concentrations of metals in the sediments listed in **Table 2**, the Yucateco and Mecoacan lagoons report high levels with respect to the three lagoons considered in this study. The Cd presented up to an order of magnitude higher

anthropogenic. However, the V was the one that reported the highest concentrations

V has their origin in the composition of the dominant oil in the area. These levels can be considered normal and expected, since there are oil wells in the vicinity of the Yucateco lagoon and Mecoacan lagoon. In **Table 2**, it is clearly observed how the variations in the concentrations of the metals analyzed are influenced by the

> **Cu (μg g<sup>−</sup><sup>1</sup> )**

), while Pb has a natural origin, by atmospheric transport, as well as

**Pollutants**

**Pb (μg g<sup>−</sup><sup>1</sup> )**

0.98 0.46 20.52 N.D 11.42 31.11 13.91 N.D 19.65

5.68 0.66 13.00 15.77 23.37 72.26 N.D 56.14 NR

2.00 N.D 13.75 17.49 27.49 71.80 N.D 55.81 36.21

6.12 0.18

3.85 1.84 36.32 48.30 53.90 1.61 57.71

0.15 1.47 28.93 21.22 58.94 18.78 5.1

**Ni (μg g<sup>−</sup><sup>1</sup> )**

origin. The Cr and Pb are up to 100% above the areas of this study (36.32 and

), this shows that Cd has a lithological as well as anthropogenic

. What is clear is that part of the Ni and

**V (μg g<sup>−</sup><sup>1</sup> )**

**Zn (μg g<sup>−</sup><sup>1</sup> )**

**OC (ng g<sup>−</sup><sup>1</sup> )** literature on this [49] and thanks to the use of sedimentary cores we know that these pollutants have been introduced to the lagoons more than 50 years ago and that their presence can originate as waste from oil activities or by the pyrolysis such as volcanism, burning of coal, burning of pastures and forest fires. Regarding its presence, the dominant PAHs are formed by four rings (pyrolytic) such as chrysene, benzo[a]anthracene, benzo[k]fluoranthene and benzo[b]fluoranthene. In general, their concentrations do not exceed the criterion of maximum concentration to cause adverse biological effects [46].
