Acute toxicity(Short term) -:  

• Respiratory tract irritation, sore throat and/or cough 
• Allergic sensitisation 
• Eye and skin irritation 
• Nausea, vomiting , diarrhea, headache  

Chronic toxicity (long term)-: 

Low doses don't always cause immidiate effects but over time they can cause very serious illness. 

• Parkinson's disease 
• Asthma 
• Depression and anxiety 
• Cancer
• Attention deficit and hyperactivity disorder 

Fortunately, they are not the only means to control the pests. There are many alternatives to chemical pesticides like-: 

• Hand picking-: It is time consuming but unbeatable. Use the gloves to remove visible offending pests and disease. 
• Trap plants-: Certain plants can be strategically placed so that they lure harmful insects away from the plants you use to protect.
• Barriers and traps: 

1. Collars:- To stop hatching larvae from burrowing into the soil sorrounding your plants use collars made of stiff paper, heavy plastic or tar paper. 
2. Netting:- Fine netting such as cheese cloth placed over bed will protect  seedlings from chewing insects and also keep cats and birds away. 
3. Sticky board:- A board of thick piece of paper painted yellow and coated with a sticky substance will attract and intercept aphids and other flying insects. 
4. Crop rotation:- Planting different kinds of Vegetables in each different section each year will help to reduce pest infestation. 
5. Companion planting:- Some plants possess natural ability to repel certain type of pests. Common planting is the practice of placing insect repellent plant next to crops that will benefit from their natural properties. 

If you must use pesticides then low toxicity pesticides should be used. Formulated, biodegradable pest control substance are commonly available. These products have low toxicity to mammals and do not last long in environment.