When purchasing shrimp, it's important to be cautious about certain types that may be harmful to health. Here are five types of shrimp that are commonly associated with contamination due to the use of harmful chemicals or growth hormones:

1. Hormone-Injected Shrimp
   These shrimp are often injected with growth hormones to make them grow faster and larger in a short amount of time. This practice can lead to residual hormones remaining in the shrimp, which, when consumed, may cause hormone imbalances in the human body.

2. Antibiotic-Treated Shrimp
   Some shrimp are treated with antibiotics to prevent diseases in crowded farming conditions. However, overuse of antibiotics can lead to antibiotic resistance and residue in the shrimp. Eating shrimp with high antibiotic levels can lead to adverse health effects, including potential resistance to medication.

3. Farmed Shrimp from Polluted Waters
   Shrimp farmed in contaminated waters are often exposed to harmful chemicals, pesticides, and other pollutants. These substances can accumulate in the shrimp’s tissues, which can pose significant health risks to consumers.

4. Imported Shrimp with Unclear Sourcing
   Imported shrimp from certain countries may not meet the same safety standards as locally sourced shrimp. These shrimp can sometimes be treated with unregulated chemicals or grown in unsafe conditions, increasing the risk of contamination.

5. Artificially Colored Shrimp
   Some shrimp are dyed to make them appear fresher or more appealing to customers. These artificial colors can be harmful to health if consumed regularly, especially when they contain non-food grade dyes.

To ensure that you are buying safe and healthy shrimp, always check the source, look for certifications that indicate safe farming practices, and avoid shrimp that may have been treated with harmful chemicals.