Foodborne Toxins: Videos & Practice Problems

Which of the following best defines 'naturally occurring food toxins' and provides correct examples?

Which statement correctly contrasts plant- and microbe-derived food toxins?

You find a potato stored in a pantry with green discoloration limited to the skin and small sprouts. Using safe handling principles, what should you do if you plan to cook it?

A small cafeteria routinely receives potatoes showing variable greening. As a food safety analyst, which policy change would most directly reduce solanine risk across lots while remaining practical?

A consumer plan: raw lima beans (150 g) contain 200 µg cyanide-equivalent per gram. Proper boiling reduces cyanide content by 92%. A can of lima beans has already been cooked during processing and contains 5 µg cyanide-equivalent per gram. Calculate and compare the total cyanide-equivalent exposure (in mg) from consuming 150 g of (A) raw beans immediately eaten without cooking, (B) the same beans after correct boiling, and (C) canned beans. Which choice correctly lists the three exposures (A, B, C) in milligrams?

Which statement correctly contrasts the risk of cyanide exposure from raw versus canned lima beans?

A hiker collects several mushroom species and wants to serve them to a group. Apply risk-analysis reasoning to select the best recommendation.

As a public health officer evaluating a community education flyer, which phrasing best communicates the risk of foraging wild mushrooms to nonexpert audiences while promoting safe behavior?

In a catered buffet, a cold chicken salad was prepared in the morning and placed on the serving table at 11:00 for a 3-hour event in a room at 25°C. Using time-temperature control principles, what is the primary food-safety problem and the best corrective action?

Analyze this kitchen workflow: workers prepare a custard-based pastry filling at 9:00, leave it at room temperature for 6 hours to cool slowly, then bake the pastries to serving at 16:00. Which specific step(s) likely led to increased risk of staphylococcal foodborne illness despite the final baking?

Which of the following statements about Clostridium botulinum and botulism is correct?

A community workshop promotes home canning using recipes from an old family cookbook. Which of the following recommendations is most important to prevent botulism and should be emphasized to participants?

Which description accurately distinguishes a 'residue' from a 'contaminant' in food-safety terminology?

Which agency primarily sets tolerance levels for pesticide residues on foods in the United States?

A pregnant client drinks well water and uses some imported ceramic cookware. Based on known heavy-metal exposure pathways, which targeted mitigation advice is most appropriate to reduce lead and mercury risk?

A family consumes canned tuna twice weekly; a child in the household is 6 years old. Apply guidance to estimate whether this consumption pattern is likely to increase the child's mercury exposure substantially and recommend an evidence-based dietary adjustment.

Design a concise dietary rule for pregnant people that integrates biomagnification principles to minimize mercury exposure from seafood, and choose the option that best synthesizes the scientific concept into actionable guidance.

Biomagnification refers to which process relevant to contaminants in aquatic food chains?

A consumer routinely microwaves leftovers in plastic containers and eats the fatty trim from beef. Provide evidence-based behavioral changes to reduce exposure to BPA and dioxins.

A dietitian is developing risk-reduction tips for a community concerned about both BPA and dioxins. Which combined recommendation most effectively addresses both contaminants based on exposure routes?

You are reviewing a policy brief claiming that washing produce is unnecessary because regulatory agencies always keep residues below levels of concern. Which critical evaluation best balances the regulatory framework with consumer-level risk reduction?

Given a modeled contaminant concentration of 0.02 mg/kg in phytoplankton and a biomagnification factor of 10 per trophic level, what is the expected contaminant concentration (mg/kg) in a top predator fish three trophic steps above phytoplankton? Use the biomagnification factor multiplicatively.

A 60 kg adult eats a 200 g portion of tuna containing 0.35 mg/kg methylmercury. Using the EPA reference dose of 0.1 µg/kg body weight per day, calculate the adult's methylmercury intake in µg/kg/day from this meal and determine whether it exceeds the EPA RfD (show calculations).

A city has older infrastructure with lead service lines. As a local nutritionist advising families, which sequence of practical steps best reduces lead exposure from household water used for drinking and cooking?

A pediatrician receives a social-media post advising the use of raw honey as a natural sleep aid for infants under 6 months. Critically evaluate and select the best professional response to give to parents.

Develop a one-sentence safety tip that synthesizes the shared prevention principle for solanine, cyanogenic glycosides, wild-mushroom toxins, staphylococcal toxins, and botulinum toxin applicable to home cooks.

Which of the following is a common consumer behavior that increases exposure to BPA?

A consumer advocacy group suggests eliminating all pesticide residues by banning modern pesticides outright. Evaluate this policy proposal by selecting the most balanced critique considering public health, agriculture, and regulation.

Which population groups are most vulnerable to nervous-system harm from lead and mercury exposures and therefore most in need of mitigation measures?

Create a concise three-step SOP (standard operating procedure) for a small baked-goods shop to prevent staphylococcal toxin formation in cream-filled pastries, integrating hygiene and time-temperature control.